N-acylamino acid derivatives

ABSTRACT

An N-acylamino acid derivative of the formula: ##STR1## wherein each of R 1 , R 2 , R 4  and R 6  is hydrogen, lower alkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl or a monocyclic or bicyclic heterocyclic group containing from 1 to 4 hetero atoms; each of R 3  and R 5  is hydrogen or lower alkyl; A is --CH(OH)--(CH 2 ) q  R 7  wherein R 7  is hydrogen, lower alkyl, cycloalkyl, cyloalkylalkyl, aryl, aralkyl, a-monocyclic or bicyclic heterocyclic group containing from 1 to 4 hetero atoms or --E--R 10  wherein E is --S(O) i  -- wherein i is 0, 1 or 2, oxygen, --NR 11  -- wherein R 11  is hydrogen, lower alkyl, cycloalkyl, cycloalkylalkyl, aryl or aralkyl, or ##STR2## wherein each of R 12  and R 13  is hydrogen, lower alkyl, cycloalkyl, cycloalkylalkyl, aryl or aralkyl, and R 10  is hydrogen, lower alkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl or a monocyclic or bicyclic heterocyclic group containing from 1 to 4 hetero atoms provided that when R 10  is hydrogen, i is 0, and a is an integer of from 0 to 5; or --CH 2  --CHR 8  --CO--R 9  wherein R 8  is hydrogen, lower alkyl, cycloalkyl, cycloalkylakyl, aryl, aralkyl or a monocyclic or bicyclic heterocyclic group containing from 1 to 4 hetero atoms, and R 9  is hydroxyl, --OX wherein, X is alkyl aryl, lower alkoxycarbonyloxyalkyl or 1-phthalidyl, or --N(Y 1 )(Y 2  ) wherein each of Y 1  and Y 2  is hydrogen, lower alkyl, aryl, aralkyl or cycloalkyl, or Y 1  and Y 2  form together with the adjacent nitrogen atom a 5- or 6-membered heterocyclic group which may contain a further hetero from; m is 0, 1 or 2; and n is an integer of from 1 to 5, provided that when R 1  is hydrogen, m is 0; or a salt thereof, which is useful as hypotensive drugs.

This is a division of application Ser. No. 07/240,725, filed on Sep. 6,1988, now U.S. Pat. No. 5,122,523.

The present invention relates to N-acylamino acid derivatives or theirsalts useful in the pharmaceutical field. More particularly, the presentinvention relates to N-acylamino acid derivatives or their salts whichhave renin inhibiting activities and which are thus expected to beuseful as hypotensive drugs.

A renin-angiotensin system is one of hypertensive systems in the livingbody, and it is an important system for regulating the bloodpressure-body fluid electrolyte. Renin is secreted from renaljuxtaglomerular cells and enters into the whole body circulation systemvia the renal vein. In the blood, there exists angiotensinogen which isa glycoprotein produced in the liver. Renin reacts on angiotensinogen toform angiotensin I. Most of angiotensin I will be converted toangiotensin II by angiotensin I-converting enzyme which is present inthe pulmonary vascular endothelial cells in one cycle of pulmonar,circulation. Angiotensin II thus formed directly induces contraction ofsmooth muscles of peripheral blood vessels and thus shows a stronghypertensive activity. It further acts on the adrenal cortex to inducesecretion of aldosterone, which in turn acts on the renal to facilitatereabsorption of sodium, whereby the effective circulatory blood flowincreases, the cardiac output increases and the peripheral vascularresistance increases so that the blood pressure increases.

It is known that hypertension will be brought about if thisrenin-angiotensin system was enhanced abnormally. Typical examples arerenal vascular hypertension and malignant hypertension. Further, as arare case, hypertension caused by a renin producing tumor is known.

For the treatment of the hypertension due to the enhancement of therenin-angiotensin system, inhibitors against the angiotensinI-converting enzyme have been studied, developed and subjected toclinical tests. However, such inhibitors are suspected to have sideeffects, since the substrate specificity of the angiotensin I-convertingenzyme is broad to some extent and there exist some enzymes similar tothe angiotensin I-converting enzyme in the living body. On the otherhand,, it is known that renin has a strict substrate specificity.Accordingly, an inhibitor against renin has a strong specificity and canbe a superior hypotensive drug. For this reason, the research on renininhibitors has been very active, and a number of renin inhibitors havebeen proposed.

However, most of these inhibitors are polypeptides, which are hardlyabsorbable by oral administration and which are susceptible todecomposition by a protease in vivo. Besides, they have highlipophilicity and are likely to be readily excreted to bile, whereby theretention of the hypotensive effects can not be expected.

On the other hand, Japanese Unexamined Patent Publication No.275258/1986 discloses dipeptides represented by the formula: ##STR3##wherein each of R¹ and R² which may be the same or different is a--B--R⁶ group wherein B is a single bond or a straight chain or branchedchain lower alkylene group which may have a double bond in the chain,and R⁶ is an aryl group or a heteroaryl group, a C₁ -C₁₀ alkyl group ora --E--R⁷ group wherein E is a lower alkylene group which may beinterrupted by one oxygen atom, and R⁷ is a lower alkoxy group, anaryloxy group, an arylthio group, an aralkyloxy group or anitrogen-containing heterocyclyl group; R³ is an ethylene, trimethyleneor tetramethylene group which may be substituted by a lower alkyl,phenyl or hydroxyl group, a ##STR4## group wherein R⁸ is anitrogen-containing heterocyclyl-substituted lower alkyl group, a C₅-C₁₈ alkyl group, a C₂ -C₅ alkenyl or C₂ -C₅ alkynyl group which may besubstituted by halogen, or a ##STR5## wherein each of R⁹ and R¹⁰ whichmay be the same or different is a lower alkyl group, or R⁹ and R¹⁰ formtogether with the adjacent carbon atom a C₃ -C₈ cycloalkyl group; R⁴ isin isopropyl group, a C₃ -C₈ cycloalkyl group or a phenyl group; R⁵ is ahydroxyl group, a C₁ -C₁₀ alkoxy group, an aryloxy group, an aminogroup, a mono- or di-(C₁ -C₁₀ alkyl)amino group (wherein the alkyl groupmay have one or two substituents which may be the same or different andwhich are selected from the group consisting of a hydroxyl group, alower alkoxy group, a halogen atom, an unsubstituted or substitutedphenyl group, a pyridyl group, a C₃ -C₈ cycloalkyl group, a di(loweralkyl)amino group, a di(hydroxy lower alkyl)amino group or anitrogen-containing heterocyclyl group), a mono or di(C₃ -C₄alkenyl)amino group, a C₃ -C₈ cycloalkylamino group, an arylamino group,a nitrogen-containing heterocyclylamino group wherein the amino andheterocyclyl are linked by N--C, a nitrogen-containing heterocyclylgroup wherein the heterocyclyl group is linked to a carbonyl group by anitrogen atom contained in the group, or a --NHR¹¹ group wherein R¹¹ isan amino group, a C₁ -C₁₀ aliphatic acylamino group which may besubstituted by a halogen atom, a lower alkoxy group, an aryloxy group,an arylacyl group, an aryl group or a C₃ -C₈ cycloalkyl group, anarylacylamino group, a cinnamoylamino group, a heteroarylacylaminogroup, a lower alkylamino group which may be substituted by a hydroxylgroup, a lower alkoxy group, a C₁ -C₅ aliphatic acyloxy group, anarylacyloxy group or an aryl group, an arylamino group or anitrogen-containing heterocyclyl group wherein the heterocyclyl group islinked to --NH-- by a nitrogen atom; R is a hydrogen atom, a C₁ -C₆aliphatic acyl group or an arylacyl group; and A is a single bond, anoxygen atom or a sulfur atom. Further, Japanese Unexamined PatentPublication No. 120370/1987 discloses dipeptide derivatives representedby the formula: ##STR6## wherein R¹ is a carbamoyl group or a loweralkoxycarbonyl group, His is a L-histidine group, n is 0 or 1, Y is--O-- or --NH--; and R² is a C₁ -C₇ straight chain or branched alkylgroup.

The compounds disclosed in the above publications have relatively shortpeptide chains and are therefore expected to have improved absorbabilityby oral administration. However, because of the short peptide chains,their renin-inhibiting activities are poor.

To reduce the molecular size is the most effective means to improve theabsorbability by oral administration to be stable against a protease invivo and to avoid the rapid excretion to bile. However, such a means islikely to lead to a substantial decrease of the renin-inhibitingactivities as shown by the above publications.

As a result of years of extensive researches on the peptide derivativesand on the renin-inhibitors, the present inventors have found thatN-acylamino acid derivatives having a novel structure exhibits strongrenin-inhibiting activities in spite of their short peptide chains, andyet they have excellent absorbability by oral administration. Thepresent invention is based on this discovery.

The present invention provides an N-acylamino acid derivative of theformula: ##STR7## wherein

each of R¹, R², R⁴ and R⁶ which may be the same or different is ahydrogen atom, a substituted or unsubstituted lower alkyl group, asubstituted or unsubstituted cycloalkyl group, a substituted orunsubstituted cycloalkylalkyl group, a substituted or unsubstituted arylgroup, a substituted or unsubstituted aralkyl group or a substituted orunsubstituted monocyclic or bicyclic heterocyclic group containing from1 to 4 hetero atoms selected from the group consisting of nitrogen,sulfur and oxygen atoms;

each of R³ and R⁵ which may be the same or different is a hydrogen atomor a lower alkyl group;

A is a --CH(OH)--CH₂)_(q) R⁷ wherein R⁷ is a hydrogen atom, asubstituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcyloalkylaikyl group, a substituted or unsubstituted aryl group, asubstituted or unsubstituted aralkyl group, a substituted orunsubstituted monocyclic or bicyclic heterocyclic group containing from1 to 4 hetero atoms selected from the group consisting of nitrogen,sulfur and oxygen atoms or a --E--R¹⁰ group wherein E is a --S(O)_(i) --group wherein i is 0, 1 or 2, an oxygen atom, a --NR¹¹ -- group whereinR¹¹ is a hydrogen atom, a substituted or unsubstituted lower alkylgroup, a substituted or unsubstituted cycloalkyl group, a substituted orunsubstituted cycloalkylalkyl group, a substituted or unsubstituted arylgroup or a substituted or unsubstituted aralkyl group, or a ##STR8##group wherein each of R¹² and R¹³ which may be the same or different isa hydrogen atom, a substituted or unsubstituted lower alkyl group, asubstituted or unsubstituted cycloalkyl group, a substituted orunsubstituted cycloalkylalkyl group, a substituted or unsubstituted arylgroup or a substituted or unsubstituted aralkyl group, and R¹⁰ is ahydrogen atom, a substituted or unsubstituted lower alkyl group, asubstituted or unsubstituted cycloalkyl group, a substituted orunsubstituted cycloalkylalkyl group, a substituted or unsubstituted arylgroup, a substituted or unsubstituted aralkyl group or a monocyclic orbicyclic heterocyclic group containing from 1 to 4 hetero atoms selectedfrom the group consisting of nitrogen, sulfur and oxygen atoms, providedthat when R¹⁰ is a hydrogen atom, i is 0, and q is an integer of from 0to 5; or a --CH₂ --CHR --CO--R⁹ group wherein R⁸ is a hydrogen atom, asubstituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcycloalkylalkyl group, a substituted or unsubstituted aryl group, asubstituted or unsubstituted aralkyl group or a substituted orunsubstituted monocyclic or bicyclic heterocyclic group containing from1 to 4 hetero atoms selected from the group consisting of nitrogen,surfur and oxygen atoms, and R is a hydroxyl group, a --OX group whereinX is a substituted or unsubstituted alkyl group, a substituted orunsubstituted aryl group, a lower alkoxycarbonyloxyalkyl group or a1-phthalidyl group, or a --N(Y¹)(Y²) group wherein each of Y¹ and Y²which may be the same or different is a hydrogen atom, a substituted orunsubstituted lower alkyl group, a substituted or unsubstituted arylgroup, a substituted or unsubstituted aralkyl group or a substituted orunsubstituted cycloalkyl group, or Y¹ and Y² form together with theadjacent nitrogen atom a 5- or 6-membered heterocyclic group which maycontain a further hetero atom selected from the group consisting ofnitrogen, oxygen and sulfur atoms;

m is 0, 1 or 2; and

n is an integer of from 1 to 5,

provided that when R¹ is a hydrogen atom, m is 0; or a salt thereof.

The present invention also provides a hypotensive drug comprising aneffective amount of an N-acylamino acid derivative of the formula I orits pharmaceutically acceptable salt and a pharmaceutically acceptablecarrier.

The N-acylamino acid derivative of the formula I can be prepared by aprocess which comprises condensing an N-acylamino acid of the formula:##STR9## wherein R¹, R², R³, R⁴, m and n are as defined above, or areactive derivative at the carboxyl group thereof with an amine of theformula: ##STR10## wherein R⁵, R⁶ and A are as defined above, orcondensing a carboxylic acid of the formula: ##STR11## wherein R¹, R², mand n are as defined above, or a reactive derivative at the carboxylgroup thereof with an amino acid amide of the formula: ##STR12## whereinR³, R⁴, R⁵, R⁶ and A are as defined above.

Further, the present invention provides novel intermediates representedby the following formulas A and B which are useful for the production ofthe compound of the formula I: ##STR13## wherein each of R¹ and R² whichmay be the same or different is a hydrogen atom, a substituted orunsubstituted lower alkyl group, a substituted or unsubstitutedcycloalkyl group, a substituted or unsubstituted cycloalkylalkyl group,a substituted or unsubstituted aryl group, a substituted orunsubstituted aralkyl group or a substituted or unsubstituted monocyclicor bicyclic heterocyclic group containing from 1 to 4 hetero atomsselected from the group consisting of nitrogen, sulfur and oxygen atoms;R¹⁴ is a carboxyl group, a reactive derivative of a carboxyl group or aprotected carboxyl group; m is 0, 1 or 2; and n is an integer of from 1to 5; provided that when R¹ is a hydrogen atom, m is 0. ##STR14##wherein R⁵ is a hydrogen atom or a lower alkyl group; R⁶ is a hydrogenatom, a substituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcycloalkylalkyl group, a substituted or unsubstituted aryl group, asubstituted or unsubstituted-aralkyl group or a substituted orunsubstituted monocyclic or bicyclic heterocyclic group containing from1 to 4 hetero atoms selected from the group consisting of nitrogen,sulfur and oxygen atoms; R⁷ is a hydrogen atom, a substituted orunsubstituted lower alkyl group, a substituted or unsubstitutedcycloalkyl group, a substituted or unsubstituted cycloalkylalkyl group,a substituted or unsubstituted aryl group, a substituted orunsubstituted aralkyl group, a substituted or unsubstituted monocyclicor bicyclic heterocyclic group containing from 1 to 4 hetero atomsselected from the group consisting of nitrogen, sulfur and oxygen atomsor a --E--R¹⁰ group, wherein E is a --S(O)_(i) -group wherein i is 0,1or 2, an oxygen atom, a --NR¹¹ -group wherein R¹¹ is a hydrogen atom, asubstituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcycloalkylalkyl group, a substituted or unsubstituted aryl group or asubstituted or unsubstituted aralkyl group, or ##STR15## wherein each ofR¹² and R¹³ which may be the same or different is a hydrogen atom, asubstituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcycloalkylalkyl group, a substituted or unsubstituted aryl group or asubstituted or unsubstituted aralkyl group, and R¹⁰ is a hydrogen atom,a substituted or unsubstituted lower alkyl group, a substituted orunsubstituted cycloalkyl group, a substituted or unsubstitutedcycloalkylalkyl group, a substituted or unsubstituted aryl group, asubstituted or unsubstituted aralkyl group or a monocyclic or bicyclicheterocyclic group containing from 1 to 4 hetero atoms selected from thegroup consisting of nitrogen, sulfur and oxygen atoms, provided thatwhen R¹⁰ is a hydrogen atom, i is 0; R¹⁵ is a hydrogen atom or aprotecting group for an amino group, each of R¹⁶ and R¹⁷ which may bethe same or different is a hydrogen atom or a protecting group for ahydroxyl group; and q is an integer of from 0 to 5.

Now, the present invention will be described in detail with reference tothe preferred embodiments.

In the accompanying drawing, FIG. 1 is a graph showing the hypotensiveactivities of the compound of the present invention as administered tomonkeys in Test Example 3 given hereinafter.

Firstly, the definitions of various terms referred to in thisspecification and some specific examples falling within such terms willbe given.

The substituted or unsubstituted lower alkyl group may be a straightchain or branched lower alkyl group having from 1 to 6 carbon atoms suchas a methyl group, an ethyl group, a propyl group, an isopropyl group, abutyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, apentyl group, a neopentyl group, an isopentyl group, a hexyl group or anisohexyl group, which is unsubstituted or substituted by a halogen atomsuch as a chlorine atom, a fluorine atom or a bromine atom; a hydroxylgroup; a lower alkoxy group such as a methoxy group, an ethoxy group, apropoxy group, an isopropoxy group, a butoxy group, an isobutoxy group,a sec-butoxy group or a tert-butoxy group; an aryloxy group such as aphenoxy group, a 1-naphthyloxy group or a 2-naphthyloxy group; anaralkyloxy group such as a benzyloxy group, a phenetyloxy group, a1-naphthylmethyloxy group or a 2-naphthylmethyloxy group; an aminogroup; a mono- or di-lower alkylamino group such as a methylamino group,an ethylamino group, a propylamino group, an isopropylamina group, abutylamino group, a sec-butylamino group, an isobutylamino group, atert-butylamino group, a dimethylamino group or a diethylamino group; anarylamino group such as a phenylamino group, a 1-naphthylamino group ora 2-naphthylamino group; an aralkylamino group such as a benzylaminogroup, a phenetylamino group, a 1-naphthylmethylamino group or a2-naphthylmethylamino group; a carboxyl group; a formyl group; a loweralkoxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonylgroup, a propoxycarbonyl group, an isopropoxycarbonyl group, abutoxycarbonyl group, a sec-butoxycarbonyl group, an isobutoxycarbonylgroup or a tert-butoxycarbonyl group; an aryloxy carbonyl group such asa phenoxycarbonyl group, a 1-naphthyloxycarbonyl group or a2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group such as abenzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto group; a lower alkylthio-group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthic group such as a phenylthio group, a1-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthiogroup or a 2-naphthylmethylthio group; an arylsulfinyl group such as aphenylsulfinyl group, a 1-naphthylsulfinyl group or a 2-naphthylsulfinylgroup; an aralkylsulfinyl group such as a benzylsulfinyl group, aphenetylsulfinyl group, a 1-naphthylmethylsulfinyl group or a2-naphthylmethylsulfinyl group; a lower alkylsulfonyl group such as amesyl group, an ethylsulfonyl group, a propylsulfonyl group, anisopropylsulfanyl group, a butylsulfonyl group, an isobutylsulfonylgroup, a sec-butylsulfonyl group or a tert-butylsulfonyl group, anarylsulfonyl group such as a phenylsulfonyl group, a 1-naphthylsulfonylgroup or a 2-naphthylsulfonyl group; an aralkylsulfonyl group such as abenzylsulfonyl group, a phenetylsulfonyl group, a1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonyl group; or aheterocyclic group such as a pyrrolyl group, a furyl group, a thienylgroup, a pyridyl group, an imidazolyl group, a pyrazolyl group, athiazolyl group, an isothiazolyl group, an isoxazolyl group, an oxazolylgroup, a pyrazinyl-group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, a quinolyl group, an isoquinolyl group, a phthalazinylgroup, a naphthidinyl group, a quinoxalinyl group, a quinazolinyl group,a 1,4-benzodioxanyl group, a 1,3-benzodioxanyl group, a 1,2,3-triazolylgroup, a 1,3,4-triazolyl group, a 1,3,4-thiadiazolyl group, a1,2,3-thiadiazolyl group, a tetrazolyl group, a tetrahydrofuranyl group,a tetrahydrothienyl group, a pyrrolidinyl group, an imidazolidinylgroup, a 2-imidazolinyl group, a morpholinyl group, a morpholino group,a morpholine N-oxide group, a lower alkyl morpholino group such as anN-methylmorpholino group, an N-ethylmorpholino group or anN-propylmorpholino group, a piperazinyl group, a piperidino group, apiperidinyl group, a thiomorpholino group or athiomorpholinyl group. Thesubstituted or unsubstituted cycloalkylalkyl group may be acycloalkylalkyl group having from 4 to 10 carbon atoms such as acyclopropylmethyl group, a cyclobutylmethyl group, a cyclopentylmethylgroup, a cyclohexylmethyl group, 1-cyclopropylethyl group, a2-cyclopropylethyl group, a 1-cyclobutylethyl group, a 2-cyclobutylethylgroup, a 1-cyclopentylethyl group, a 2-cyclopentylethyl group, a1-cyclohexylethyl group, a 3-cyclohexylpropyl group, a3-cyclopentylpropyl group, a 4-cyclohexylbutyl group or a4-cyclopentylbutyl group, which is unsubstituted or substituted by ahalogen atom such as a chlorine atom, a fluorine atom or a bromine atom;a hydroxyl group; a lower alkyl group such as a methyl group, an ethylgroup, a propyl group, an isopropyl group, a butyl group, an isobutylgroup, a sec-butyl group or a tert-butyl group; a lower alkoxy groupsuch as a methoxy group, an ethoxy group, a propoxy group, an isopropoxygroup, a butoxy group, an isobutoxy group, a sec-butoxy group or atert-butoxy group; an aryloxy group such as a phenoxy group, a1-naphthyloxy group or a 2-naphthyloxy group; an aralkyloxy group suchas a benzyloxy group, a phenetyloxy group, a 1-naphthylmethyloxy groupor a 2-naphthylmethyloxy group; an amino group; a mono- or di-loweralkylamino group such as a methylamino group, an ethylamino group, apropylamino group, an isopropylamino group, a butylamino group, asec-butylamino group, an isobutylamino group, a tert-butylamino group, adimethylamino group or a diethylamino group; an arylamino group such asa phenylamino group, a 1-naphthylamino group or a 2-naphthylamino group;an aralkylamino group such as a benzylamino group, a phenetylaminogroup, a 1-naphthylmethylamino group or a 2-naphthylmethylamino group; acarboxyl group; a formyl group; a lower alkoxycarbonyl group such as amethoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group,an isopropoxycarbonyl group, a butoxycarbonyl group, asec-butoxycarbonyl group, an isobutoxycarbonyl group or atert-butoxycarbonyl group; an aryloxy carbonyl group such as aphenoxycarbonyl group, a 1-naphthyloxycarbonyl group or a2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group such as abenzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto group; a lower alkylthio group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthio group such as a phenylthio group, a1-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthiogroup or a 2-naphthylmethylthio group; an arylsulfinyl group such as aphenylsulfinyl group, a 1-naphthylsulfinyl group or a 2-naphthylsulfinylgroup; an aralkylsulfinyl group such as a benzylsulfinyl group, aphenetylsulfinyl group, a 1-naphthylmethylsulfinyl group or a2-naphthylmethylsulfinyl group; a lower alkylsulfonyl group such as amesyl group, an ethylsulfonyl group, a propylsulfonyl group, anisopropylsulfonyl group, a butylsulfonyl group, an isobutylsulfonylgroup, a sec-butylsulfonyl group or a tert-butylsulfonyl group; anarylsulfonyl group such as a phenylsulfonyl group, a 1-naphthylsulfonylgroup or a 2-naphthylsulfonyl group; an aralkylsulfonyl group such as abenzylsulfonyl group, a phenetylsulfonyl group, a1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonyl group; or aheterocyclic group such as a pyrrolyl group, a furyl group, a thienylgroup, a pyridyl group, an imidazolyl group, a pyrazolyl group, athiazolyl group, an isothiazolyl group, an isoxazolyl group, an oxazolylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, a quinolyl group, an isoquinolyl group, a phthalazinylgroup, a naphthidinyl group, a quinoxalinyl group, a quinazolinyl group,a 1,4-benzodioxanyl group, a 1,3-benzodioxanyl group, a 1,2,3-triazolylgroup, a 1,3,4-triazolyl group, a 1,3,4-thiadiazolyl group, a1,2,3-thiadiazolyl group, a tetrazolyl group, a tetrahydrofuranyl group,a tetrahydrothienyl group, a pyrrolidinyl group, an imidazolidinylgroup, a 2-imidazolinyl group, a morpholinyl group, a morpholino group,a morpholine N-oxide group, a lower alkyl morpholino group such as anN-methylmorpholino group, an N-ethylmorpholino group or anN-propylmorpholino group, a piperazinyl group, a piperidino group, apiperidinyl group, a thiomorpholino group or a thiomorpholinyl group.The substituted or unsubstituted cycloalkyl group may be a cycloalkylgroup having from 3 to 6 carbon atoms such as a cyclopropyl group, acyclobutyl group, a cyclopentyl group or a cyclohexyl group, which isunsubstituted or substituted by a halogen atom such as a chlorine atom,a fluorine atom or a bromine atom; a hydroxyl group; a lower alkyl groupsuch as a methyl group, an ethyl group, a propyl group, an isopropylgroup, a butyl group, an isobutyl group, a sec-butyl group or atert-butyl group; a lower alkoxy group such as a methoxy group, anethoxy group, a propoxy group, an isopropoxy group, a butoxy group, anisobutoxy group, a sec-butoxy group or a tert-butoxy group; an aryloxygroup such as a phenoxy group, a 1-naphthyloxy group or a 2-naphthyloxygroup; an aralkyloxy group such as a benzyloxy group, a phenetyloxygroup, a 1-naphthylmethyloxy group or a 2-naphthylmethyloxy group; anamino group; a mono- or di-lower alkylamino group such as a methylaminogroup, an ethylamino group, a propylamino group, an isopropylaminogroup, a butylamino group, a sec-butylamino group, an isobutylaminogroup, a tert-butylamino group, a dimethylamino group or a diethylaminogroup; an arylamino group such as a phenylamino group, a 1-naphthylaminogroup or a 2-naphthylamino group; an aralkylamino group such as abenzylamino group, a phenetylamino group, a 1-naphthylmethylamino groupor a 2-naphthylmethylamino group; a carboxyl group; a formyl group; alower alkoxycarbonyl group such as a methoxycarbonyl group, anethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonylgroup, a butoxycarbonyl group, a sec-butoxycarbonyl group, anisobutoxycarbonyl group or a tert-butoxycarbonyl group; an aryloxycarbonyl group such as a phenoxycarbonyl group, a 1-naphthyloxycarbonylgroup or a 2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group suchas a benzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto group; a lower alkylthio group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthio group such as a phenylthio group, a1-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthiogroup or a 2-naphthylmethylthio group; an arylsulfinyl group such as aphenylsulfinyl group, a 1-naphthylsulfinyl group or a 2-naphthylsulfinylgroup; an aralkylsulfinyl group such as a benzylsulfinyl group, aphenetylsulfinyl group, a 1-naphthylmethylsulfinyl group or a2-naphthylmethylsulfinyl group; a lower alkylsulfonyl group such as amesyl group, an ethylsulfonyl group, a propylsulfonyl group, anisopropylsulfonyl group, a butylsulfonyl group, an isobutylsulfonylgroup, a sec-butylsulfonyl group or a tert-butylsulfonyl group; anarylsulfonyl group such as a phenylsulfonyl group, a 1-naphthylsulfonylgroup or a 2-naphthylsulfonyl group; an aralkylsulfonyl group such as abenzylsulfonyl group, a phenetylsulfonyl group, a1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonyl group; or aheterocyclic group such as a pyrrolyl group, a furyl group, a thienylgroup, a pyridyl croup, an imidazolyl group, a pyrazolyl group, athiazolyl group, an isothiazolyl group, an isoxazolyl group, an oxazolylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, a quinolyl group, an isoquinolyl group, a phthalazinylgroup, a naphthidinyl group, a quinoxalinyl group, a quinazolinyl group,a 1,4-benzodioxanyl group, a. 1,3-benzodioxanyl group, a 1,2,3-triazolylgroup, a 1,3,4-triazolyl group, a 1,3,4-thiadiazolyl group, a1,2,3-thiadiazolyl group, a tetrazolyl group, a tetrahydrofuranyl group,a tetrahydrothienyl group, a pyrrolidinyl group, an imidazolidinylgroup, a 2-imidazolinyl group, a morpholinyl group, a morpholino group,a morpholine N-oxide group, a lower alkyl morpholino group such as anN-methylmorpholino group, an N-ethylmorpholino group or anN-propylmorpholino group, a piperazinyl group, a piperidino group, apiperidinyl group, a thiomorpholino group or a thiomorpholinyl group.

The substituted or unsubstituted aryl group may be an aryl group havingfrom 6 to 15 carbon atoms such as a phenyl group, a biphenylyl group, a1-naphthyl group or a 2-naphthyl group, which is unsubstituted orsubstituted by a halogen atom such as a chlorine atom, a fluorine atomor a bromine atom; a nitro group; a hydroxyl group; a lower alkyl groupsuch as a methyl group, an ethyl group, a propyl group, an isopropylgroup, a butyl group, an isobutyl group, a sec-butyl group or atert-butyl group; a lower alkoxy group such as a methoxy group, anethoxy group, a propoxy group, an isopropoxy group, a butoxy group, anisobutoxy group, a sec-butoxy group or a tert-butoxy group; an aryloxygroup such as a phenoxy group, a 1-naphthyloxy group or a 2-naphthyloxygroup; an aralkyloxy group such as a benzyloxy group, a phenetyloxygroup, a 1-naphthylmethyloxy group or a 2-naphthylmethyloxy group; anamino group; a mono- or di-lower alkylamino group such as a methylaminogroup, an ethylamino group, a propylamino group, an isopropylaminogroup, a butylamino group, a sec-butylamino group, an isobutylaminogroup, a tert-butylamino group, a dimethylamino group or a diethylaminogroup; an arylamino group such as a phenylamino group, a 1-naphthylaminogroup or a 2-naphthylamino group; an aralkylamino group such as abenzylamino group, a phenetylamino group, a 1-naphthylmethylamino groupor a 2-naphthylmethylamino group; a carboxyl group; a formyl group; alower alkoxycarbonyl group such as a methoxycarbonyl group, anethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonylgroup, a butoxycarbonyl group, a sec-butoxycarbonyl group, anisobutoxycarbonyl group or a tert-butoxycarbonyl group; an aryloxycarbonyl group such as a phenoxycarbonyl group, a 1-naphthyloxycarbonylgroup or a 2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group suchas a benzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto, group; a lower alkylthio group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthio group such as a phenylthio group, a1-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthio group or a 2-naphthylmethylthio group; anarylsulfinyl group such as a phenylsulfinyl group, a 1-naphthylsulfinylgroup or a 2-naphthylsulfinyl group; an aralkylsulfinyl group such as abenzylsulfinyl group, a phenetylsulfinyl group, a1-naphthylmethylsulfinyl group or a 2-naphthylmethylsulfinyl group; alower alkylsulfonyl group such as a mesyl group, an ethylsulfonyl group,a propylsulfonyl group, an isopropylsulfonyl group, a butylsulfonylgroup, an isobutylsulfonyl group, a sec-butylsulfonyl group or atert-butylsulfonyl group; an arylsulfonyl group such as a phenylsulfonylgroup, a 1-naphthylsulfonyl group or a 2-naphthylsulfonyl group; anaralkylsulfonyl group such as a benzylsulfonyl group, a phenetylsulfonylgroup, a 1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonylgroup; or a heterocyclic group such as a pyrrolyl group, a furyl group,a thienyl group, a pyridyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an isoxazolyl group, anoxazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, a quinolyl group, an isoquinolyl group, aphthalazinyl group, a naphthidinyl group, a quinoxalinyl group, aquinazolinyl group, a 1,4-benzodioxanyl group, a 1,3-benzodioxanylgroup, a 1,2,3-triazolyl group, a 1,3,4-triazolyl group, a1,3,4-thiadiazolyl group, a 1,2,3-thiadiazolyl group, a tetrazolylgroup, a tetrahydrofuranyl group, a tetrahydrothienyl group, apyrrolidinyl group, an imidazolidinyl group, a 2-imidazolinyl group, amorpholinyl group, a morpholino group, a morpholine N-oxide group, alower alkyl morpholino group such as an N-methylmorpholino group, anN-ethylmorpholino group or an N-propylmorpholino group, a piperazinylgroup, a piperidino group, a piperidinyl group, a thiomorpholino groupor a thiomorpholinyl group.

The substituted or unsubstituted aralkyl group may be an aralkyl grouphaving from 7 to 15 carbon atoms such as a benzyl group, a1-naphthylmethyl group, a 2-naphthylmethyl group, a5,6,7,8-tetrahydro-1-naphthyl group, a 5,6,7,8-tetrahydro-2-naphthylgroup, a phenetyl group, a 3-phenylpropyl group or a 4-phenylbutylgroup, which is unsubstituted or substituted by a halogen atom such as achlorine atom, a fluorine atom or a bromine atom; a nitro group; ahydroxyl group; a lower alkyl group such as a methyl group, an ethylgroup, a propyl group, an isopropyl group, a butyl group, an isobutylgroup, a sec-butyl group or a tert-butyl group; a lower alkoxy groupsuch as a methoxy group, an ethoxy group, a propoxy group, an isopropoxygroup, a butoxy group, an isobutoxy group, a sec-butoxy group or atert-butoxy group; an aryloxy group such as a phenoxy group, a1-naphthyloxy group or a 2-naphthyloxy group; an aralkyloxy group suchas a benzyloxy group, a phenetyloxy group, a 1-naphthylmethyloxy groupor a 1-naphthylmethyloxy group; an amino group; a mono- or di-loweralkylamino group such as a methylamino group, an ethylamino group, apropylamino group, an isopropylamino group, a butylamino group, asec-butylamino group, an isobutylamino group, a tert-butylamino group, adimethylamino group or a diethylamino group; an arylamino group such asa phenylamino group, a 1-naphthylamino group or a 2-naphthylamino group;an aralkylamino group such as a benzylamino group, a phenetylaminogroup, a 1-naphthylmethylamino group or a 2-naphthylmethylamino group; acarboxyl group; a formyl group; a lower alkoxycarbonyl group such as amethoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group,an isopropoxycarbonyl group, a butoxycarbonyl group, asec-butoxycarbonyl group, an isobutoxycarbonyl group or atert-butoxycarbonyl group; an aryloxy carbonyl group such as aphenoxycarbonyl group, a 1-naphthyloxycarbonyl group or a2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group such as abenzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto group; a lower alkylthio group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthio group such as a phenylthio group, ai-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthiogroup or a 2-naphthylmethylthio group; an arylsulfinyl group such as aphenylsulfinyl group, a 1-naphthylsulfinyl group or a 2-naphthylsulfinylgroup; an aralkylsulfinyl group such as a benzylsulfinyl group, aphenetylsulfinyl group, a 1-naphthylmethylsulfinyl group or a2-naphthylmethylsulfinyl group; a lower alkylsulfonyl group such as amesyl group, an ethylsulfonyl group, a propylsulfonyl group, anisopropylsulfonyl group, a butylsulfonyl group, an isobutylsulfonylgroup, a sec-butylsulfonyl group or a tert-butylsulfonyl group; anarylsulfonyl group such as a phenylsulfonyl group, a 1-naphthylsulfonylgroup or a 2-naphthylsulfonyl group; an aralkylsulfonyl group such as abenzylsulfonyl group, a phenetylsulfonyl group, a1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonyl group; or aheterocyclic group such as a pyrrolyl group, a furyl group, a thienylgroup, a pyridyl group, an imidazolyl group, a pyrazolyl group, athiazolyl group, an isothiazolyl group, an isoxazolyl group, an oxazolylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindolyl group, a quinolyl group, an isoquinolyl group, a phthalazinylgroup, a naphthidinyl group, a quinoxalinyl group, a quinazolinyl group,a 1,4-benzodioxanyl group, a 1,3-benzodioxanyl group, a 1,2,3-triazolylgroup, a 1,3,4-triazolyl group, a 1,3,4-thiadiazolyl group, a1,2,3-thiadiazolyl group, a tetrazolyl group, a tetrahydrofuranyl group,a tetrahydrothienyl group, a pyrrolidinyl group, an imidazolidinylgroup, a 2-imidazolinyl group, a morpholinyl group, a morpholino group,a morpholine N-oxide group, a lower alkyl morpholino group such as anN-methylmorpholino group, an N-ethylmorpholino group or anN-propylmorpholino group, a piperazinyl group, a piperidino group, apiperidinyl group, a thiomorpholino group or a thiomorpholinyl group.The substituted or unsubstituted monocyclic or bicyclic heterocyclicgroup containing from 1 to 4 hetero atoms selected from the groupconsisting of nitrogen, sulfur and oxygen atoms, may be a heterocyclicgroup such as a pyrrolyl group, a furyl group, a thienyl group, apyridyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an isoxazolyl group, an oxazolyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an indolylgroup, a quinolyl group, an isoquinolyl group, a phthalazinyl group, anaphthidinyl group, a quinoxalinyl group, a quinazolinyl group, a1,4-benzodioxanyl group, a 1,3-benzodioxanyl group, a 1,2,3-triazolylgroup, a 1,3,4-triazolyl group, a 1,3,4-thiadiazolyl group, a1,2,3-thiadiazolyl group, a tetrazolyl group, a tetrahydrofuranyl group,a tetrahydrothienyl group, a pyrrolidinyl group, an imidazolidinylgroup, a 2-imidazolinyl group, a morpholinyl group, a morpholino group,a piperizine N-oxide group, a piperazine N-oxide group, a morpholineN-oxide group, a lower alkyl morpholino group such as anN-methylmorpholino group, an N-ethylmorpholino group or anN-propylmorpholino group, a piperazinyl group, a piperidino group, apiperidinyl group, a thiomorpholino group or a thiomorpholinyl group,which is unsubstituted or substituted by a halogen atom such as achlorine atom, a fluorine atom or a bromine atom; a nitro group; ahydroxyl group; a lower alkyl group such as a methyl group, an ethylgroup, a propyl group, an isopropyl group, a butyl group, an isobutylgroup, a sec-butyl group or a tert-butyl group; a triphenylmethyl group;a lower alkoxy group such as a methoxy group, an ethoxy group, a propoxygroup, an isopropoxy group, a butoxy group, an isobutoxy group, asec-butoxy group or a tert-butoxy group; an aryloxy group such as aphenoxy group, a 1-naphthyloxy group or a 2-naphthyloxy group; anaralkyloxy group such as a benzyloxy group, a phenetyloxy group, a1-naphthylmethyloxy group or a 2-naphthylmethyloxy group; an aminogroup; a mono- or di-lower alkylamino group such as a methylamino group,an ethylamino group, a propylamino group, an isopropylamino group, abutylamino group, a sec-butylamino group, an isobutylamino group, atert-butylamino group, a dimethylamino group or a diethylamino group; anarylamino group such as a phenylamino group, a 1-naphthylamino group ora 2-naphthylamino group; an aralkylamino group such as a benzylaminogroup, a phenetylamino group, a 1-naphthylmethylamino group or a2-naphthylmethylamino group; a carboxyl group; a formyl group; a loweralkoxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonylgroup, a propoxycarbonyl group, an isopropoxycarbonyl group, abutoxycarbonyl group, a sec-butoxycarbonyl group, an isobutoxycarbonylgroup or a tert-butoxycarbonyl group; an aryloxy carbonyl group such asa phenoxycarbonyl group, a 1-naphthyloxycarbonyl group or a2-naphthyloxycarbonyl group; an aralkyloxycarbonyl group such as abenzyloxycarbonyl group, a phenetyloxycarbonyl group, a1-naphthylmethyloxycarbonyl group or a 2-naphthylmethyloxycarbonylgroup; a mercapto group; a lower alkylthio group such as a methylthiogroup, an ethylthio group, a propylthio group, an isopropylthio group, abutylthio group, a sec-butylthio group, an isobutylthio group or atert-butylthio group; an arylthio group such as a phenylthio group, a1-naphthylthio group or a 2-naphthylthio group; an aralkylthio groupsuch as a benzylthio group, a phenetylthio group, a 1-naphthylmethylthiogroup or a 2-naphthylmethylthio group; an arylsulfinyl group such as aphenylsulfinyl group, a 1-naphthylsulfinyl group or a 2-naphthylsulfinylgroup; an aralkylsulfinyl group such as a benzylsulfinyl group, aphenetylsulfinyl group, a 1-naphthylmethylsulfinyl group or a2-naphthylmethylsulfinyl group; a lower alkylsulfonyl group such as amesyl group, an ethylsulfonyl group, a propylsulfonyl group, anisopropylsulfonyl group, a butylsulfonyl group, an isobutylsulfonylgroup, a sec-butylsulfonyl group or a tert-butylsulfonyl group; anarylsulfonyl group such as a phenylsulfonyl group, a 1-naphthylsulfonylgroup or a 2-naphthylsulfonyl group; or an aralkylsulfonyl group such asa benzylsulfonyl group, a phenetylsulfonyl group, a1-naphthylmethylsulfonyl group or a 2-naphthylmethylsulfonyl group.

In the --N(Y¹)(Y²) group, when Y¹ and Y² form together with the adjacentnitrogen atom a 5- or 6-membered heterocyclic group which may contain afurther hetero atom selected from the group consisting of nitrogen,oxygen and sulfur atoms, such a heterocyclic group may be, for example,a morpholino group, a thiomorpholino group, a piperidino group, apyrrolidinyl group or a piperazinyl group.

The lower alkoxycarbonyloxyalkyl group may be a loweralkyloxycarbonylalkyl group having from 3 to 9 carbon atoms such as amethoxycarbonyloxymethyl group, an ethoxycarbonyloxymethyl group, apropoxycarbonyloxymethyl group, an isopropoxycarbonyloxymethyl group, abutoxycarbonyloxymethyl group, a tert-butoxycarbonyloxymethyl group, a1-methoxycarbonyloxyethyl group, a 2-methoxycarbonyloxyethyl group, a1-ethoxycarbonyloxyethyl group, a 2-ethoxycarbonyloxyethyl group, a1-tert-butoxycarbonyloxyethyl group, a 2-tert-butoxycarbonyloxyethylgroup, a 1-butoxycarbonyloxyethyl group, a 1-pentylcarbonyloxyethylgroup or a 1-hexylcarbonyloxyethyl group.

In the compound of the formula I of the present invention, theasymmetric carbon atoms may have R-configuration, S-configuration orRS-configuration.

The salt of the compound of the present invention may be anypharmaceutically acceptable non-toxic salt. For example, it may be asalt with anion such as CP.sup.⊕, P.sup.⊕, Br.sup.⊕ or I.sup.⊕ with-aninorganic acid such as hydrochloric acid, sulfuric acid, hydrobromicacid, hydriodic acid or phosphoric acid, or a salt with an organic acidsuch as oxalic acid, maleic acid, acetic acid, formic acid or tartaricacid.

Representative compounds of the present invention are listed in Tables Aand B, wherein Et means ethyl, ^(i) P, isopropyl, ^(n) Bu n-butyl, ^(i)Bu isobutyl, ^(t) Bu tert-butyl, Tri triphenylmethyl, Zbenzyloxycarbonyl and Nap-CH₂ -1-naphthylmethyl, and each of A, B, C, Dand E indicates the steric configuration (R, S or RS).

    TABLE A      ##STR16##       R.sup.1' R.sup.2' R.sup.3' R.sup.4 ' R.sup.5' R.sup.6' R.sup.8'     R.sup.9' m' n' A B C D E       Et NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 2 1 R or S S S S R     S      ##STR17##      NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 2 1 R or S S S S RS     Et      ##STR18##      H CH.sub.2 CH.sub.2 CH.sub.2 OH H .sup.i Bu Et NH.sup.i Bu 2 1 R or S S     S S RS      ##STR19##      NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 2 1 R or S S S S S      ##STR20##      NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 0 1 S S S S RS      ##STR21##      NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 0 1 S S S S RS      ##STR22##      NapCH.sub.2 H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 1 1 S S S S RS  Et     NapCH.sub.2 H .sup.n Bu H .sup.i      Bu Et     ##STR23##      2 1 R or S S S S R or S      Et     ##STR24##      H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 2 1 S S S S RS      Et     ##STR25##      H .sup.n Bu H .sup.i Bu Et NH.sup.i Bu 2 1 S S S S RS      Et     ##STR26##      H      ##STR27##      H .sup.i Bu Et NH.sup.i Bu 2 1 S S S S RS  Et NapCH.sub.2 H .sup.n Bu H     .sup.i Bu Et NH.sup.i Bu 0 3 R or S S S S RS Et NapCH.sub.2 H .sup.n Bu     H .sup.i Bu Et NH.sup.i Bu 2 3 R or S S S S RS  Et NapCH.sub.2 H      ##STR28##      H .sup.i Bu Et NH.sup.i Bu 2 1 RS S S S RS      Et NapCH.sub.2 H     ##STR29##      H .sup.i Bu Et NH.sup.i      Bu 2 1 S S S S RS

    TABLE B      ##STR30##       R.sup.1' m' n' R.sup.2' R.sup.3' R.sup.4' R.sup.5' R.sup.6' q'     R.sup.7' A B C D E                      Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR31##      1      ##STR32##       S S RS RS  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR33##      1      ##STR34##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR35##      1      ##STR36##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n Bu H .sup.i      Bu 1     ##STR37##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR38##      1 NHCH.sub.2 CH.sub.2 OCH.sub.3 S S S R S  Et 2 1 NapCH.sub.2 H .sup.n     Bu H      ##STR39##      1 SCH.sub.3 S S S R or S RS  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR40##      1 NHCH.sub.2 CH.sub.2 OH S S S R S  Et 2 1 NapCH.sub.2 H .sup.n Bu H      ##STR41##      1      ##STR42##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR43##      1      ##STR44##      S S S RS RS  Et 2 1 NapCH.sub.2 H .sup.n Bu H .sup.i Bu 1 S.sup.i Pr S     S S RS RS  Et 2 1 NapCH.sub.2 H .sup.n Bu H .sup.i      Bu 1     ##STR45##      S S S RS RS  Et 2 1 .sup.i Bu H .sup.n      Bu H     ##STR46##      1      ##STR47##      S or R S S R S  Et 0 3 NapCH.sub.2 H .sup.n      Bu H     ##STR48##      1      ##STR49##      S or R S S R S  Et 2 3 NapCH.sub.2 H .sup.n      Bu H     ##STR50##      1      ##STR51##      S or R S S R S      Et 2 1     ##STR52##      H .sup.n      Bu H     ##STR53##      1      ##STR54##      S S S R S      Et 2 1 NapCH.sub.2 H     ##STR55##      H      ##STR56##      1      ##STR57##      S S S R S  Et 2 1 NapCH.sub.2 H CH.sub.2      OH H     ##STR58##      1      ##STR59##      S S S R S  Et 2 1 NapCH.sub.2 H CH.sub.2 CH.sub.2      SCH.sub.3 H     ##STR60##      1      ##STR61##      S S S R S  .sup.i      Pr 2 1     ##STR62##      H .sup.i      Bu H     ##STR63##      1      ##STR64##      S S S R S  .sup.i      Pr 1 1 NapCH.sub.2 H     ##STR65##      H      ##STR66##      1      ##STR67##      S S S R S  HOCH.sub.2 CH.sub.2 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR68##      1      ##STR69##      S or R S S R S      Et 2 1     ##STR70##      H .sup.n      Bu H     ##STR71##      1      ##STR72##      S S S R S  .sup.t Bu 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR73##      1      ##STR74##      S S S R S      ##STR75##      2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR76##      1      ##STR77##      S S S R S      ##STR78##      0 1 NapCH.sub.2 H .sup.n      Bu H     ##STR79##      1      ##STR80##      S S S R S      ##STR81##      2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR82##      1      ##STR83##      S S S R S      ##STR84##      1 1 NapCH.sub.2 H .sup.n      Bu H     ##STR85##      1      ##STR86##      S S S R S      ##STR87##      2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR88##      1      ##STR89##      S S S R S      ##STR90##      2 1      ##STR91##      H .sup.n      Bu H     ##STR92##      1      ##STR93##      S S S R S  Et 2 1 NapCH.sub.2 H CH.sub.2 CH.sub.2 OCOCH.sub.3 H      ##STR94##      1      ##STR95##      S S S R S  Et 2 1 NapCH.sub.2 H CH.sub.2 CH.sub.2      OH H     ##STR96##      1      ##STR97##      S S S R S      ##STR98##      2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR99##      1      ##STR100##      S S S R S  HOCH.sub.2 CH.sub.2 1 1 NapCH.sub.2 H .sup.n      Bu H     ##STR101##      1      ##STR102##      S or R S S R S  Et 1 1 NapCH.sub.2 H .sup.n      Bu H     ##STR103##      1      ##STR104##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR105##      1      ##STR106##      S S S R S      ##STR107##      2 1 PhCH.sub.2 H .sup.n      Bu H     ##STR108##      1      ##STR109##      S or R S S R S      ##STR110##      2 1 PhCH.sub.2 H .sup.n      Bu H     ##STR111##      1      ##STR112##      S S S R S      ##STR113##      2 1 PhCH.sub.2 H .sup.n      Bu H     ##STR114##      1      ##STR115##      S S S R S      Et 2 1     ##STR116##      H .sup.n      Bu H     ##STR117##      1      ##STR118##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR119##      1      ##STR120##      S S S R S  Et 2 1 NapCH.sub.2 H .sup.n      Bu H     ##STR121##      1      ##STR122##      S S S R S      Et 2 1     ##STR123##      H .sup.n      Bu H     ##STR124##      1      ##STR125##      S S S R S      Et 2 1     ##STR126##      H .sup.n      Bu H     ##STR127##      1      ##STR128##      S S S R S

Now, the process for the preparation of the compound of the formula I ofthe present invention will be described.

In the following formulas, R¹, R², R³, R⁴, R⁵, R⁶, m, n and A are asdefined above, and T is a leaving group.

Basically, the N-acylamino acid derivative of the formula I of thepresent invention can be prepared by condensing an N-acylamino acid ofthe formula: ##STR129## or a reactive derivative at the carboxyl groupthereof with an amine of the formula: ##STR130## or condensing acarboxylic acid of the formula: ##STR131## or a reactive derivative atthe carboxyl group thereof with an amino acid amide of the formula:##STR132##

The condensation of the compounds of the formulas II and III or thecondensation of the compounds of the formulas IV and V can be conductedby a usual method for the synthesis of a peptide, such as an azidemethod, an active ester method, a mixed acid anhydride method, acarbodiimide method, an imidazole method, a diphenylphosphoryl azidemethod, a Woodward method or condensation method in an oxidation andreduction system.

When a functional group which may adversely affect the condensationreaction, such as an amino group, or a carboxyl group, is present, sucha functional group may be protected and then condensed, and theprotecting group is then removed to obtain the compound of the presentinvention. Such a condensation method, protection of a functional groupand removal of the functional group are disclosed in detail, forexample, in "Basic for the Peptide Synthesis and Experiments" edited byNobuo Izumiya et al, Maruzen (1985), "Protein Chemistry I" edited byShiro Akabori et al, Kyoritsu Shuppan (1969), or "Chemistry of the AminoAcids" edited by J. P. Greenstein and M. Winitz, John Wiley & Sons, Inc.(1961).

The compound of the formula II can be prepared by the process shown byreaction scheme I. ##STR133##

To a dialkyl malonate, a halide such as 1-(chloromethyl)naphthalene isreacted at room temperature in a solvent such as tetrahydrofuran in thepresence of a bass such as sodium hydride to obtain a compound of theformula 2, which is then subjected to a saponification reaction at roomtemperature in ethanol by means of e.g. potassium hydroxide or sodiumhydroxide to obtain a half ester of the formula 3. If this hydrolyticreaction is conducted by means of an enzyme such as esterlise or lipase,or an insolubilized enzyme thereof, it is possible to obtain anoptically active half ester of the formula 3.

The compound of the formula 3 is condensed with an amino acid having aprotected carboxyl group by the above-mentioned usual method for thepeptide synthesis, to obtain a compound of the formula 4. As a preferredembodiment, a tert-butyl ester of an amino acid and the compound of theformula 3 are condensed at room temperature in dimethylformamide bymeans of N,N'-dicyclohexylcarbodiimide in the presence of1-hydroxybenzotriazole. Depending upon the purpose, the compound of theformula 4 is subjected to an extension of the carbon chain, for example,by the method shown by reaction scheme 2. ##STR134##

The compound of the formula 4 has two ester moieties. By differenciatingthe types of the ester moieties, it is possible to convert only one ofthe ester moieties to a carboxylic acid group. For example, by selectingan ethyl group for R and a tert-butyl group for R', it is possible tohydrolyze only the ethyl ester moiety by saponification with an alkali.The resulting carboxylic acid compound of the formula 10 may beconverted to an acid anhydride or to an acid halide by a usual methodand then reacted with a diazomethane to obtain a diazoketone compound ofthe formula 11, which is then reacted with a silver compound such assilver benzoate or silver oxide dissolved in triethylamine,, in a loweralkanol such as methanol or ethanol to obtain a compound of the formula12 having the carbon number increased by one. By repeating thisreaction, it is possible to obtain a compound of the formula 5 havingvarious carbon numbers. The compound of the formula 5 has two estermoieties. By differenciating the types of the ester moieties, it ispossible to reduce only one of the ester moieties. For example, by usingan ethyl group for R and a tert-butyl group for R', it is possible toobtain the desired compound of the formula 6 by the reduction withsodium borohydride in ethanol at room temperature. To facilitate thethioetherification, the hydroxyl group formed by the reduction of theester of the compound of the formula 5 is converted to an excellent.leaving group shown by T such as a tosyloxy group, a mesyloxy group or ahalogen. This step can readily be conducted by reacting p-toluenesulfonyl chloride to the compound of the formula 6 at room temperaturein the presence of a base such as pyridine. Then, the compound of theformula 7 and a thiol compound are reacted usually at room temperaturein the presence of a base such as sodium hydride in a solvent such asdimethylformamide to obtain a compound of the formula 8. The oxidationof the compound of the formula 8 can be conducted by a usual method, forexample, with a manganese compound, chromic acid, a lead compound, ahalogen, hydrogen peroxide, an organic per acid, an inorganic nitrogencompound or an organic compound such as dimethylsulfoxide. By selectingthe oxidizing agent or reaction conditions, a sulfoxide compound(compound wherein m 1) and a sulfone compound (compound wherein m=2) canbe prepared, respectively. For example, when a compound of the formula 8is oxidized at room temperature by means of an aqueous hydrogen peroxidesolution in a solvent such as methanol by using sodium tungstate as acatalyst, a sulfonic compound (compound wherein m=2) can be obtained. Byremoving the protecting-group from the compound of the formula 9 by amethod suitable for the removal of the particular protecting group,compound of the formula II can be obtained. Further, the stericchemistry on the carbon to which R² is bonded, can be freely controlledby utilizing the Sharpless oxidation reaction, for example, by a methodrepresented by Reaction scheme 3. ##STR135##

In the above formulas, R², R³, R⁴, R' and n are as defined above, and p¹and p² represent hydroxyl-protecting groups.

An allylic alcohol of the formula 13 is subjected to asymmetricepoxidation in accordance with the method disclosed by A. Pfenninger in"Synthesis" p80-116 (1986). Then, the hydroxyl group is protected by ahydroxyl-protecting group p², and then the epoxy ring is selectivelyopened by a Grignard reagent. Then, p² is removed. Then, oxidation isconducted by e.g. sodium periodate to obtain a carboxylic acid, which isthen condensed with an amino acid having a protected carboxylic acid bya usual method for peptide synthesis such as a dicyclohexylcarbodiimidemethod. Then, the hydroxy-protecting group p¹ is removed to obtain thecompound of the formula 6 having the desired steric coodination. Thehydroxyl-protecting group p¹ is preferably a benzyl group, and p² ispreferably a tert-butyldimethylsilyl group.

Further, the synthesis can be conducted stereoselectivly also by thefollowing Reactive scheme 4. ##STR136## wherein R¹, R², m and n are asdefined above, and D is an optically active amine. A compound of theformula 20 obtained by reacting a fatty acid having a mercapto group atthe terminal with R¹ - X wherein X is a halogen such as bromine, isconverted to a mixed acid anhydride by using e.g. pivaloyl chloride andthen condensed with an optically active compound such as(4R,5S)-4-methyl-5-phenyl-2-oxazolidinone in the presence of e.g.n-butyl lithium. Then, R² -X wherein X is a halogen such as bromine isreacted thereto by using a base such as lithium diisopropylamide tostereospecifically introduce the R² group. Then, if necessary, after anaddition of hydrogen peroxide, the product is hydrolyzed with an alkalito obtain a compound of the formula 23. If necessary, by using asuitable oxidizing agent such as hydrogen peroxide, a sulfoxide compound(a compound wherein m is 1) or sulfonic compound (compound wherein m is2) can be obtained. The optically active compound of the formula D maybe recovered and again used for the reaction.

Some of the compounds of the formula II can also be prepared by aprocess shown by Reaction scheme 5. ##STR137##

In the above formulas, R^(2') is a substituent of R² wherein the1-position is methylene group, such as a naphthylmethyl group. AHorner-Emmon's reagent of the formula 1' and an aldehyde are reactedusually at room temperature preferably under an inert gas stream such asargon or nitrogen in a solvent which does not adversely affect thereaction, such as tetrahydrofuran or dimethylformamide, if necessary, byan addition of an alkali metal or alkaline earth metal halide such aslithium chloride, lithium bromide or magnesium bromide and by a furtheraddition of a base e.g. a tertiary amine such as diazabicycloundecene,triethylamine or diisopropylethylamine or an alkali metal halide,hydroxide, alcoholate or alkyl compound such as sodium hydride, sodiumhydroxide, sodium ethoxide or butyl lithium, to obtain a compound of theformula 2'. The hydroxyl-protecting group W' may be a commonly employedhydroxyl-protecting group such as a tetrahydropyranyl group, a tritylgroup or a benzyl group, but preferably is a tetrahydropyranyl group. Asthe Horner-Emmon's reagent, any reagent equivalent to the compound ofthe formula 1' may be employed. The compound of the formula 2' iscatalytically reduced under atmospheric pressure or elevated pressure inthe presence of a metal catalyst such as palladium black,palladium-carbon or platinum oxide to obtain a compound of the formula3', followed by the removal of the protective group to obtain a compoundof the formula 4'. Steps 4, 5 and 6 can be conducted in the same manneras Steps 6, 7 and 8, respectively, of Reaction scheme 1. Thesaponification of Step 7 can be conducted in a usual manner, forexample, saponification with an alkali such as sodium hydroxide in asolvent mixture of water and a lower alkanol, to obtain a compound ofthe formula 8'. The condensation of Step 8 can be conducted in the samemanner as Step 3 in Reaction scheme 1. Then, the removal of theprotective group is conducted to obtain a compound of the formula II.

The compound of the formula II can be prepared by a process shown byReaction scheme 6 in the case of a compound wherein A is ##STR138##

In the above formulas, R¹⁸ is an amino-protecting group, and R¹⁹ is ahydroxyl-protecting group. The compound of the formula 24 can beprepared by a method disclosed in J. Med. Chem., Vol. 30, p.976-982(1987). The compound of the formula 24 is reacted with R⁷ --(CH₂)_(q)--MgX wherein X is chlorine or bromine, and R⁷ is as defined above in asolvent such as dry tetrahydrofuran at a temperature of from -78° C. toroom temperature, to obtain a compound of the formula 25. By removingthe protective group, a compound of the formula III can be obtained.

Some of the compounds can also be prepared by a process shown byReaction scheme 7. ##STR139##

The compound of the formula 26 is a starting material for thepreparation of the compound of the formula 24, and the method for thepreparation thereof is also disclosed in J. Med, Chem., Vol 30,p.976-982 (1987). The compound of the formula 26 is reacted with anoxidizing agent such as m-chloro perbenzoic acid at room temperature ina solvent such as methylene chloride to obtain a compound of the formula27, which is then reacted with a nucleophilic reagent B such as a thiolcompound to obtain a compound of the formula 28. By the removal of aprotecting group, a compound of the formula 3 can be obtained.

Some of the compounds of the formula III can be preparedstereospecifically by utilizing the asymmetric center of a saccharide bya process as shown by Reaction scheme 8. ##STR140##

In the above formulas, R⁶ ' corresponds to R⁶ except that it is shorterthan R⁶ by one methylene, and p¹, p² and P³ are hydroxy-protectinggroups, and G represents an amine compound.

The starting material 1,2:5,6-diisopropylidene-α-D-allofuranose canreadily be prepared from a D-glucose by a method disclosed by J. D.Stevens in "Methods in Carbohydrate Chemistry", Vol. VI, p.123 (1972).After protecting the hydroxyl group at the 3-position by p¹, only the5,6-isopropylidene was selectively removed by means of e.g. acetic acid.Then, by means of a suitable oxidizing agent such as sodium periodate,the product is converted to an aldehyde. Then, a desired side chain isintroduced by Wittig reaction. If necessary, the olefin is reduced bymeans of e.g. Raney nickel. The 1,2-isopropylidene is removed bytreatment with an acid in a lower alcohol, and at the same time, thehydroxyl group at the 1-position is protected by p². Further, thehydroxyl group at the 2-position is protected by p³, and then thehydroxyl-protecting group p² at the 1-position is removed. An aminecompound G such as morpholine is added, and the amino alkylationreaction is conducted by means of a metal hydride complex compound suchas sodium cyano borohydride. Then, the free hydroxyl group at the4-position is stereoinverslbly converted to an azide group by means ofdiphenylphospholyl azide in the presence of suitable azide-formingagents, preferably triphenylphosphine and diethyl azodicarboxylate. Thisazide group is reduced to an amino group in a usual manner. Then, thehydroxyl-protecting groups p¹ and p³ are removed. Thus, some of thecompounds of the formula III can be stereospecifically prepared. Abenzyl group may be mentioned as a preferred example for thehydroxyl-protecting group p¹ or p³, and a methyl group may be mentionedas a preferred example for the hydroxyl protecting group p².

Further, as shown by a typical example in Reaction scheme 9 such astereospecific synthesis can be conducted by the above Sharplessasymmetric epoxidation reaction by using an optically inactive compoundas the starting material. ##STR141##

In the above formulas, R^(6'), T, B, p¹, p² and p³ are as defined above.

1,4-Pentadien-3-ol of the formula 41 prepared from vinyl magnesiumbromide and methyl formate, is subjected to the above-mentionedSharpless asymmetric epoxidation reaction to obtain an epoxy compound ofthe formula 42. After protecting the hydroxyl group by p¹, the epoxyring is selectively opened by means of a Grignard reagent R^(6') MgX,and the side chain is introduced. After protecting the formed hydroxylgroup by p², a hydroxyl group is stereoselectively introduced by anoxidizing agent such as osmium tetraoxide to obtain a-compound of theformula 46. A leaving group such as a tosyl group or a mesyl group isbonded to the primary hydroxyl group, followed by treatment with analkali such as potassium carbonate, whereby an epoxy compound of theformula 48 can be stereospecifically obtained. This compound of theformula 48 can also be prepared by removing the hydroxyl-protectinggroup p¹ of the compound of the formula 45, followed by the abovesharpless asymmetric epoxidation reaction and against protecting thehydroxyl group by p¹. A nucleophilic reagent B such as a thiol compoundor an amine compound is reacted to the compound of the formula 48, andthe formed hydroxyl group is protected by p³, and thehydroxyl-protecting group P² is removed to obtain a compound of theformula 51. A compound of the formula III can be stereospecificallyprepared from the compound of the formula 51 in the same manner as shownby the process steps 37→38→39→40 as shown in Reaction Scheme 8.

Further, the compound of the formula III wherein A is ##STR142## can beprepared by the process shown by Reaction scheme 10. ##STR143## Thecompound of the formula 24 is reacted with the Horner-Emmon's reagentpreferably in an inert gas stream such as argon or nitrogen in a solventwhich does not adversely affect the reaction, such as tetrahydrofuran ordimethylformamide, if necessary by an addition of an alkali metal oralkaline earth metal halide such as lithium chloride, lithium bromide ormagnesium bromide and further by an addition of a base, for example, atertiary amine such as diazabicycloundecene, triethylamine ordiisopropylethylamine or an alkali metal hydride, hydroxide, alcoholateor alkyl compound such as sodium hydride, sodium hydroxide, sodiumethoxide or butyl lithium, usually at room temperature, to obtain acompound of the formula 53. The Horner-Emmon's reagent may be anyreagent so long as it is equivalent to ##STR144## The ester of thecompound of the formula 53 is hydrolyzed at room temperature with sodiumhydroxide or potassium hydroxide in e.g. a solvent mixture of a loweralkanol and water to obtain a carboxylic acid of the formula 54. Then,this carboxylic acid is converted to a reactive derivative such as ahalide, an acid anhydride, an active ester or an azide by a usual methodand then reacted with an amine compound or an alcohol compound to obtaina compound of the formula 55. In this condensation step, any one of theabove peptide syntheses can be employed. In a preferred embodiment, thecompound of the formula 54 is dissolved in an anhydrous solvent such asdimethylformamide, and triethylamine, diphenylphospholyl azide and analkylamine were added at a low temperature at a level of -20° C. toconduct a reaction at room temperature to obtain a compound of theformula 55. The compound of the formula 55 is catalytically reduced inthe presence of e.g. palladium black, palladium-carbon or platinum oxideunder atmospheric 10 pressure or elevated pressure to obtain a compoundof the formula 56. Then, the protecting group is removed to obtain acompound of the formula III. Depending upon the type of the protectinggroup, the step of this catalytic reduction and the step of removal ofthe protecting group can be conducted simultaneously.

The compound of the formula IV can be prepared in the same manner as inReaction scheme 1 except that the condensation step 3 is omitted.Namely, the compound of the formula 3 is converted to ##STR145## and thesubsequent steps are the same as the steps 4→5→6→7→98→9 to obtain acompound of the formula IV.

The compound of the formula V can readily be obtained by condensing anamino-protecting amino acid and the compound of the formula III inaccordance with a usual method for the peptide synthesis, followed byremoval of the protecting group.

When the compound of the present invention is to be used as a medicine,it may be administered by itself, but it is usually administered as amixture with a carrier suitably selected depending upon the route foradministration and standard formulations. For example, for oraladministration, the compound of the present invention may beadministered in the form of tablets which may be prepared by adding to apowder of the active ingredient of the present invention an excipientsuch as starch, lactose, sucrose, glucose, crystalline cellulose,calcium carbonate or kaolin, a binder such as a starch solution, agelatin solution, a hydroxypropyl cellulose, a glucose solution, asucrose solution, water or ethanol, a disintegrator such as starch,agar, gelatin powder, carboxymethyl cellulose calcium (CMC-Ca),carboxymethyl cellulose sodium (CMC-Na), crystalline cellulose, calciumcarbonate or sodium hydrogencarbonate, or a lubricant such as magnesiumstearate, calcium stearate, talc, macrogoal 4,000, macrogoal 6,000 orstearic acid, subjecting the mixture to compression molding by aconventional tabletting method, and if necessary applying a sugarcoating by means of a concentrated sugar solution containing e.g. gumarabic, talc, polyvinyl pyrrolidone, polyethylene glycol and/or titaniumoxide, applying a film coating by means of a film-forming agent composedof e.g. polyvinyl acetal, diethylaminoacetate, cellulose acetate,N,N-dibutylaminohydroxypropyl ether, hydroxypropylmethyl cellulose,hydroxypropyl cellulose, ethyl cellulose or polyvinyl pyrrolidone, orapplying an enteric coating by means of a film-forming agent composed ofe.g. ethyl cellulose phthalate cerac, cellulose acatate phthalate orhydroxypropylmethyl cellulose phthalate; granules or fine granules whichmay be prepared by adding to the active ingredient of the presentinvention a binder such as starch, gelatin, gum arabic, methylcellulose, sodium carboxymethyl cellulose, heavy silicic anhydride orlight silicic anhydride, followed by kneading and granulation by usualmethods; a powder of the active ingredient of the present invention byitself; or capsules which may be prepared by adding to the activeingredient of the present invention an excipient such as lactose, starchor crystalline cellulose and/or a lubricant such as magnesium stearate,calcium stearate or talc, and filling the mixture into capsules. Fornon-oral administration, an injection formulation may be used wherein anemulsifying agent such as propylene glycol, polyethylene glycol or avegetable oil such as olive oil, or a solubilization agent such assodium benzoate, sodium salicylate, N-hydroxyethyllactamide, calciumα-saccharide, mannitol, nicotic acid amide or cyclodextrin, is suitablyused.

Further, to such formulations, other medicinal substances may beincorporated. Such medicinal substances include, for example,acetazolamide, amiloride, chlorothiazide, furosemide, timolol,propranolol, cetamolol, clonidine, methyldopa, minoxydil, hydralazine,captopril, pivalopril, enalapril, lidinopril, verapamil, nifedipine,nicardipine, felodipine, nimodipine and diltiazem.

An advantageous formulation contains from about 0.1 mg to 500 mg of thecompound of the present invention. A preferred range of a daily dose fororal administration is from about 0.1 mg/kg to 500 mg/kg, and such adaily dose may be administered at once or in three times a day. Fornon-oral administration, it is preferred to administer the compound ofthe present invention in an amount of from about 0.1 mg/kg to 10 mg/kgper day at once. The dose may be increased or reduced by a doctor'sprescription depending upon e.g. the sex and diseased condition of thepatient.

Now, the present invention will be described in further detail withreference to the Test Example for renin inhibiting activities of thecompounds of the present invention and Working Examples.

TEST EXAMPLE 1: Renin inhibiting activities

To 156 μl of a 0.2M sodium phosphate buffer solution (pH7.4), 40 μl of asolution mixture of 34 mm 8-hydroxyquinoline and 100 mM disodiumethylenediamine tetraacetate, 4 μl of dimethyl sulfoxide or a dimethylsulfoxide solution of an inhibitor and 200 μl of human plasma were addedand reacted at 37° C. for one hour. Then, pepstatin was added thereto toterminate the reaction, and the amount of the resulting angiotension Iwas measured by radio immunoassay whereby the inhibiting activity wasdetermined. The 50% inhibition concentrations (IC₅₀ values) of thecompounds of the present invention are shown below.

                  TABLE 1                                                         ______________________________________                                        Tested Compounds       IC.sub.50 (M)                                          ______________________________________                                        Compound of Example 1  5.0 × 10.sup.-10                                 Compound of Example 2  1.7 × 10.sup.-10                                 Compound of Example 4  9.6 × 10.sup.-10                                 Compound of Example 5  1.4 × 10.sup.-9                                  Compound of Example 6  1.6 × 10.sup.-9                                  Compound of Example 7  8.3 × 10.sup.-10                                 Compound of Example 8  1.5 × 10.sup.-9                                  Compound of Example 10 2.0 × 10.sup.-9                                  Compound of Example 11 3.1 × 10.sup.-9                                  Compound of Example 12 9.7 × 10.sup.-9                                  Compound of Example 13 1.9 × 10.sup.-9                                  Compound of Example 15 5.0 × 10.sup.-10                                 Compound of Example 16 3.4 × 10.sup.-9                                  Compound of Example 19 8.3 × 10.sup.-9                                  Compound of Example 21 8.9 × 10.sup.-9                                  Compound of Example 31 4.2 × 10.sup.-9                                  Compound of Example 35 5.9 × 10.sup.-9                                  Compound of Example 36 2.7 × 10.sup.-9                                  Compound of Example 38 5.9 × 10.sup.-9                                  Compound of Example 40 5.3 × 10.sup.-9                                  Compound of Example 41 1.7 × 10.sup.-9                                  Compound of Example 42 3.6 × 10.sup.-9                                  Compound of Example 44 3.8 × 10.sup.-9                                  Compound of Example 47 2.3 × 10.sup.-9                                  Compound of Example 49(A)                                                                            6.1 × 10.sup.-9                                  Compound of Example 51(B)                                                                            2.0 × 10.sup.-9                                  Compound of Example 52 3.0 × 10.sup.-9                                  Compound of Example 56 2.0 × 10.sup.-9                                  ______________________________________                                    

From the above results, it is evident that the compounds of the presentinvention have remarkably strong% inhibiting activities against humanplasma renin.

TEST EXAMPLE 2 Absorption test by oral administration

10 mg/kg of the compound of Example 16 was orally administered to rats(n=4), whereupon the concentration of the compound in the plasma wasmeasured. The concentration in the plasma was calculated by theinhibiting activities against human plasma renin. The results are shownin Table 2.

                  TABLE 2                                                         ______________________________________                                                Time (hrs.)                                                                   1/12 1/6    1/4    1/2  1    2   4   8   24                           ______________________________________                                        Concentration                                                                           89     136    212  267  183  85  34  12  7                          of the                                                                        compound of                                                                   Example 16                                                                    (ng/ml)                                                                       ______________________________________                                    

It is evident from Table 2 that the compound of the present invention isefficiently absorbed by oral administration and shows a continualconcentration in blood.

TEST EXAMPLE 3 Hypotensive activities in monkeys

The hypotensive activities were measured in accordance with a methoddisclosed in J. Cardiovascular Pharmacology, Vol. 7, (Suppl. 4) S58-S61(1985). Namely, 30 mg/kg of furosemido (diuretic) was intracutaneouslyinjected to three marmosets i.e. small size monkeys to produce a highrenin active state. To these marmosets, 30 mg/kg of the compound ofExample 16 was orally administered, whereupon the hypotensive activitieswere measured. The results are shown in FIG. 1.

It is evident from FIG. 1 that the compound of the present inventionexhibits hypotensive activities by the oral administration. Thus, thecompound of the present invention has properties useful as a medicine.

Now, the present invention will be described in further detail withreference to Examples. However, it should be understood that the presentinvention is by no means restricted to such specific Examples.

EXAMPLE 1 (2RS,4S,5S)-B-{L-N-[(2R orS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide. (1) Ethyl (1-naphthylmethyl)malonate

(a) Into a reactor, 1 g of sodium hydride (60% in oil) was introducedand washed a few times with dry n-hexane. Then, it was dried in dryargon to dry powder, and then 10 ml of dry tetrahydrofuran (hereinafterreferred to simply as THF) was promptly added thereto and the reactorwas sealed under an argon stream. While cooling the reaction-solutionwith ice, 4.2 ml of diethyl malonate was dropwise added. Generation ofhydrogen started, but ended upon completion of the dropwise addition,whereby a uniform transparent reaction solution was obtained. Thereaction solution was returned to room temperature, then stirred for 15minutes and again cooled with ice. To this reaction solution a solutionof 4.86 g of 1-(chloromethyl)naphthalene in 5 ml of dry THF was dropwiseadded. The mixture was returned to room temperature and stirredovernight.

Then, the reaction solution was diluted with 200 ml of ethyl acetate andwashed with 100 ml of water and then with 100 ml of a saturated sodiumchloride aqueous solution. The organic layer was separated, dried overanhydrous magnesium sulfate and concentrated under reduced pressure. Thesyrup thereby obtained was purified by silica gel column chromatography(n-hexane/ethyl acetate 10/1) to obtain 5.61 g (yield: about 64%) ofdiethyl (1-naphthylmethyl)malonate as crude syrup.

Rf value (measured by silica gel plate Merck 5715, the same applieshereinafter): 0.3 (n-hexane/ethyl acetate 10/1)

Nuclear magnetic resonance spectrum (hereinafter referred to simply asNMR.) (300 MHz, CDCl₃): δppm: 1.2(6H,t,J=7Hz), 3.7(2H,d,J=8Hz),3.84(1H,dd,J=6.5,8Hz), 4.15(4H,m)

(b) 5.32 g-of the syrup of diethyl (1-naphthylmethyl)malonate wasdissolved in 20 ml of absolute ethanol. To this solution, a solution of1.17 g of potassium hydroxide (85%) in 45 ml of absolute ethanol wasdropwise added over a period of 1.5 hours. Thereafter,, the stirring wascontinued overnight. Then, the resulting suspension was weakly acidifiedwith 3 ml of 6N hydrochloric acid under cooling with ice, and 20 ml ofwater was further added thereto. Then, the mixture was concentratedunder reduced pressure at a temperature of not higher than 40° C. Theconcentrated suspension after sufficient evaporation of ethanol wasdissolved in 300 ml of ethyl acetate. The solution was washedsequentially with 200 ml of water and with 200 mi of a saturated sodiumchloride aqueous solution. The ethyl acetate layer was separated, driedover anhydrous magnesium sulfate and then concentrated under reducedpressure. The syrup thereby obtained was purified by silica gel columnchromatography (benzene/ethanol/acetic acid =100/4/0.5). The purifiedfractions of the eluted solutions were collected (about 200 ml), and 100ml of ethyl acetate was added thereto to bring the total volume to about300 ml. The mixture was thoroughly washed with a saturated sodiumchloride aqueous solution (200 ml×3 times). The organic layer was driedover anhydrous sodium sulfate. The inorganic salt was filtered off, andthe filtrate was concentrated and dried to obtain 3.64 g of ethyl(1-naphthylmethyl)malonate.

Rf: 0.54 (benzene/ethanol/acetic acid=10/1/0.5)

NMR (300 MHz, CDCl₃):

δppm: 1.16(3H,t,J=7Hz), 3.73(2H), 3.90(1H,dd,J=6.5,8Hz), 4.16(m,2H)

(2) L-norleucine tert-butyl ester

2.0 g of L-norleucine was introduced into a pressure tube, and about 30ml of dry dioxane was added thereto to obtain a suspension. Then, 2 mlof concentrated sulfuric acid was added thereto, and the reactor wascooled to -75° C. Then, isobutene gas was blown thereinto. When about 10ml of isobutene gas was introduced, the tube was sealed. The temperaturewas gradually returned to room temperature under stirring, and then thestirring was continued overnight. Then, the reactor was opened, andisobutene was evaporated under atmospheric pressure. Then, the reactionsolution was poured into 200 ml of a 2M sodium hydroxide aqueoussolution under cooling with ice, and the mixture was vigorously stirred.Then, was extracted with diethyl ether (250 ml×2 times). The separatedether layer was washed with a saturated sodium chloride aqueous solution(100 ml×2 times) and then dried over anhydrous magnesium sulfate. Theinorganic salt was filtered off, and the filtrate was concentrated toobtain a syrup. The syrup was thoroughly dried under reduced pressureand then stored at a temperature of not higher than 5° C., whereby 1.46g (yield: 51%) of the above identified compound precipitated as whitecrystals.

Rf: 0.71 (chloroform/methanol/conc.aqueous ammonia (10/0.5/0.2)

NMR (300 MHz, CDCl₃): δppm: 0.9(3H,m), 1.2-1.8(15H,m), 3.29(1H)

(3) L-N-{2-ethoxycarbonyl-3-(1-naphthyl)procionyl}norleucine tert-butylester

1.59 g of ethyl (1-naphthylmethyl)malonate was dissolved in 15 ml ofanhydrous dimethylformamide (hereinafter referred to simply as DMF).Then, a solution of 1.20 g of L-norleucine tert-butyl ester in 5 ml ofdry DMF was added thereto. The reaction solution was cooled to -15° C.,and 1.28 g of 1-hydroxybenzotriazole and 1.68 g ofN,N-dicyclohexylcarbodiimide (hereinafter referred to simply as DCC)were added thereto. The mixture was stirred for 1 hour at -15° C. andthen stirred overnight at room temperature. Then, precipitateddicyclohexylurea was filtered off, the collected filtration product waswashed with a small amount of a solvent mixture of n-hexane/ethylacetate (4/1) and the washing solutions were put together. The filtratewas diluted with 200 mi of ethyl acetate and then washed sequentiallywith 150 ml of a 4% sodium hydrogencarbonate aqueous solution and with150 ml of a saturated sodium chloride aqueous solution. The separatedethyl acetate layer was dried over anhydrous magnesium sulfate. Theinorganic salt was filtered off, and the filtrate was concentrated underreduced pressure. The syrup thereby obtained was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=4/1). The eluted fractionswere collected, concentrated under reduced pressure and dried to obtain2.45 g (yield: 95%) of the above identified compound as gelled solid.

Rf: 0.41, 0.35 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 0.89(3H,t,J=7Hz), 1.07(3H,t,J=7Hz),1.14-1.58(13H), 1.65(1H,m), 1.82(1H,m), 3.59-3.82(3Hm), 4.06(2H,m),4.45(1H,m), 6.92(1H,d,J=8Hz), 7.34(2H,m), 7.46-7.61(2H,m), 7.73(1H,m),7.85(1H,d,J=8Hz), 8.06(1H,d,J=8Hz)

(4) L-N-{(2R or S)-2-hydroxymethyl-3-(1-naphthyl)propionyl)norleucinetert-butyl ester

2.45 9 of L-N-(2-ethoxycarbonyl-3-(1-naphthyl)propionyl}norleucinetert-butyl ester was dissolved in 60 ml of ethanol. Then, 1.48 g ofsodium borohydride was gradually added thereto. The mixture was stirredfor 5.5 hours and then concentrated under reduced pressure at atemperature of not higher than 40° C. to obtain a suspension syrup. Thesyrup was dissolved in 250 ml of ethyl acetate and then washed with 200ml of water and then with 200 ml of a saturated sodium chloride aqueoussolution. The organic layer was separated and dried over anhydrousmagnesium sulfate. Then, the inorganic salt was filtered off, and thefiltrate was concentrated under reduced pressure to obtain a solid. Theproduct was purified by silica gel column chromatography (n-hexane/ethylacetate=1/1-2/1). Among the purified fractions, the fraction having a Rfvalue of 0.58 (n-hexane/ethyl acetate=1/1) was collected and extracted.The extract solution was concentrated and-dried to obtain 0.74 g (yield:33%) of crystalline solid. Further, the fraction having a Rf value of0.45 (under the same condition as in the case of the Rf value of 0.58)was collected and concentrated to obtain 0.97 g (yield: 44%) ofcrystalline solid.

Product having a Rf value of 0.58:

NMR (300 MHz, CDCl₃): δppm: 0.86(3H,t,J=7Hz), 1.15-1.38(4H), 1.43(9H,s),1.6(1H,m), 1.8(2H,m), 2.78(2H,m), 3.33(1H,dd,J=7.5,14Hz),3.49(1H,dd,J=7.5,14Hz), 3.82(2H,m), 4.37(1H,m), 6.12(1H,br s,J=7Hz),7.38(2H,d,J=5Hz), 7.45-7.57(2H,m), 7.74(1H,m), 7.86(1H,d,J=8Hz),8.05(1H,d,J=8Hz)

Melting point: 94°-95° C.

Angle of rotation [α]_(D) ²⁰ +50.5° (C 1.00, CHCl₃)

Product having a Rf value of 0.45

NMR (300 MHz, CDCl₃): δppm: 0.82(3H,t,J=7Hz), 0.85-1.0(2H,m),1.12-1.22(2H,m), 1.36-1.56(11H,m), 2.79(1H,m), 3.27(2H,m),3.48(1H,dd,J=9,14Hz), 3.86(2H,t,J=6Hz), 4.36(1H,m), 5.74(1H,br d,J=8Hz),7.37(2H,m), 7.51(2H,m), 7.73(1H,m), 7.86(1H,dd,J=1.5,8Hz),8.02(1H,d,J=8Hz)

Melting point: 92°-94° C.

Angle of rotation [a]_(D) ²⁰ =-72.6° (C 1.00, CHCl₃)

(5) L-N-1(2R orS)-2-(1-naphthylmethyl)-3-p-toluene-sulfonyloxypropionyl}norleucinetert-butyl ester

202 mg of the solid of L-N-{(2R orS)-3-hydroxy-2-(1-naphthylmethyl)propionyl}norleucine tert-butyl ester,(the product having a Rf value of 0.58 obtained in the Process (4)) wasdissolved in 3 ml of dry pyridine. Then, 107 mg of p-toluenesulfonylchloride was added thereto, and the mixture was reacted at roomtemperature for 24 hours. 15 mg of the same reagent was additionallyadded thereto, and the mixture was reacted for further 24 hours. Then,the reaction solution was concentrated under reduced pressure. Theresidue was dissolved in 20 ml of ethyl acetate and then washedsequentially with 10 ml of a 4% potassium hydrogen sulfate aqueoussolution, with 10 ml of a 4% sodium hydrogencarbonate, aqueous solutionand with 10 ml of a saturated sodium chloride aqueous solution. Theorganic layer was separated and dried over anhydrous magneisum sulfate.Then, the inorganic salt was removed by filtration, and the filtrate wasconcentrated under reduced pressure. The residue was purified by silicagel column chromatography (n-hexane/ethyl acetate =4/1), and the elutedsolution was concentrated and dried under reduced pressure to obtain 264mg of L-N-{(2R or S)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl}-nocleucine tert-butyl ester as colorlesstransparent syrup.

Rf: 0.44 (n-hexane/ethyl acetate =3/1) NMR (300 MHz, CDCl₃): δppm:0.86(3H,t,J=7Hz), 1.05-1.4(4H,m), 1.39(9H,s), 1.52(1H,m), 1.70(1H,m),2.44(3H,,s), 2.93(1H,m), 3.28(2H,m), 4.15(1H,dd,J=6,10Hz), 4.28(2H,M),5.78(1H,d,J=8Hz), 7.19-7.38(5H,m), 7.51(2H,m), 7.72(2H,M), 7.85(1H,m),7.93(1H,m)

(6) L-N-{(2R or S)-3-ethylthio-2-(1-naphthylmethyl)-propionyl}norleucinetert-butyl ester

30 mg of L-N-{(2R or S)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl}norleucine tert-butyl ester was dissolved in 0.2 ml of dryDMF. Separately, a suspension of a thioalkoxide (in 1.8 ml of dry DMF)prepared from 64 mg of sodium hydride and 0.3 ml of ethyl mercaptan, wasprepared, and 0.5 ml of the suspension was added to the above solution.The mixture was reacted at room temperature for 30 minutes, and thenabout 1 ml of water was added. Then, the reaction solution was dilutedby an addition of 20 ml of benzene and washed sequentially with 10 ml ofwater and with 10 ml of a saturated sodium chloride aqueous solution.The organic layer was separated and dried over anhydrous magnesiumsulfate, and then concentrated and dried under reduced pressure toobtain 23 mg of L-N-{(2R orS)-3-ethylthio-2-(1-naphthylmethyl)propionyl}norleucine tert-butyl esteras colorless transparent syrup.

Rf: 0.56 (n-hexane/ethyl acetate 3/1)

NMR (300 MHz, CDCl₃): δppm: 0.88(3H,t,J=7Hz), 1.1-1.4(7H,m), 1.41(9H,s),1.59(1H,m), 1.75(1H,m), 2.51(1H,m), 2.72(2H,m), 2.93(1H,m),3.39(2H,d,J=6.5Hz), 4.36(1H,m), 5.86(1H,d,J=7Hz), 7.35(2H,m),7.52(2H,m), 7.72(1H), 7.85(1H), 8.07(1H)

Infrared absorption spectrum (hereinafter referred to simply as IR)(KBr)

νcm⁻¹ : 1740, 1660, 1540, 1520, 1390, 1160

(7) L-N-{(2R orS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}norleucine tert-butylester

23 mg of L-N-{(2R orS)-3-ethylthio-2-(1-naphthylmethyl)propionyl}norleucine tert-butyl esterwas dissolved in 1 ml of methanol. To this solution, 0.1 ml of a 30%hydrogen peroxide aqueous solution and sodium tungstate dehydrate wereadded, and the mixture was stirred at room temperature for 1 hour. Then,the reaction solution was diluted with 20 mi of ethyl acetate and washedsequentially with 10 ml of water and with 10 ml of a saturated sodiumchloride aqueous solution. The organic layer was separated and driedover anhydrous magnesium sulfate, and then concentrated and dried underreduced pressure to obtain 22 mg of the above identified compound ascolorless transparent syrup.

Rf: 0.12 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7Hz), 1.1-1.35(7H,m),1.38(9H,s), 1.59(1H,m), 1.72(1H,m), 2.82(2H,m), 3.01(1H,dd,J=3,14.5Hz),3.26(1H,m), 3.41(2H,m), 3.70(1H,dd,J=9,14.5Hz), 5.97(1H,d,J=7Hz),7.30(1H,d,J=6Hz), 7.38(1H,t,J=8Hz), 7.54(2H,m), 7.75(1H,d,J=8Hz),7.86(1H,d,J=8Hz), 8.02(1H,d,J=8.5Hz)

IR (KBr, neat): νcm⁻¹ : 1740, 1660, 1540, 1310, 1160, 1110

Mass spectrum (FAB-MS) 420, 476 (M⁺ +1)

(8) (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide.hydrochloride

(a) 856 mg of a sodium hydride (60% in oil) was washed three times withn-hexane under a nitrogen atmosphere. After drying, the obtained powderwas suspended in 7.2 mi of dry DMF under a nitrogen atmosphere, and 4.26mi of ethyl diethylphosphono acetate was dropwise added thereto over aperiod of one hour under stirring at 0° C. After stirring at roomtemperature for about one hour, the mixture was cooled to 0° C., and1.92 mi of bromoethane was added thereto under stirring. The mixture wasthen stirred overnight at 55° C. The reaction solution was poured into40 mi of water and extracted three times with 20 ml of ethyl acetate.The organic layer was washed with water and then with a saturated sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Then,the solvent was distilled off under reduced pressure. The residue waspurified by silica gel column chromatography (n-hexane/acetone=4/1) toobtain 2.76 g of ethyl 2-diethylphosphonobutanoate as oily substance.

Rf: 0.63 (n-hexane/ethyl acetate=1/5)

Mass spectrum m/z 253 (M⁺ +1)

NMR (60 MHz, CDCl₃): δppm: 0.95(3H,t,J=8Hz), 1.25(3H,t,J=8Hz)1.29(6H,t,J=7Hz), 1.6-2.1(2H,m), 2.8(1H,ddd,J=22,7,7Hz),4.05(2H,q,J=8Hz), 4.15(2H,q,J=7Hz)

(b)3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoicacid isobutylamide

71.6 mg of lithium chloride was suspended in 5 ml of dry THF under anargon atmosphere, and 426 mg of ethyl 2-diethylphosphonobutanoatedissolved in 0.6 ml of dry THF was added thereto under stirring. Themixture was stirred at room temperature for 5 minutes, and then 323 mgof 1,8-diazabicyclo[5,4,0]-7-undecene (hereinafter referred to simply asDBU) was added thereto in the form of a 50: dry THF solution, and themixture was stirred at room temperature for 10 minutes. Then, 450 mg of(4S,5R)-3-benzyloxycarbonyl-2,2-dimethyl-5-formyl-4-isobutyloxazolidinedissolved in 1.0 ml of dry THF was added thereto, and the mixture wasstirred at room temperature overnight. The reaction solution was cooledto 0° C. and neutralized with 1N hydrochloric acid. Then, the solutionwas extracted three times with ethyl acetate. The organic layer waswashed with water and with a saturated sodium chloride aqueous solutionand dried over anhydrous sodium sulfate. The solvent was distilled offunder reduced pressure, and the residue was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=10/1) to obtain 518 mg ofethyl3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoateas colorless oily substance.

Rf: 0.53 (n-hexane/ethyl acetate=5/1) δNMR (60 MHz, CDCl₃): δppm:0.7-1.8(21H,m),2.32(2H,M), 3.80(1H,m), 4.20(2H,q,J=7Hz),4.58(0.5H,dd,J=2,9Hz), 5.10(0.5H,M), 5.11(2H,s), 5.85(0.5H,br d,J=9Hz),6.66(0.5H,d,J=9Hz), 7.30(5H,s)

517 mg of ethyl3-1(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoatewas dissolved in 3.10 ml of an ethanol/water (9/1) solution of 2Npotassium hydroxide, and the solution was stirred at room temperaturefor 3 hours. Then, the reaction solution was adjusted to pH2 with 1Nhydrochloric acid under cooling with ice and after an addition of 24 mlof water, extracted three times with 20 ml of ethyl acetate. The organiclayer was washed with water and with a saturated sodium chloride aqueoussolution and dried over anhydrous sodium sulfate. The solvent wasdistilled off under reduced pressure to obtain3-((4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoicacid as colorless oily substance.

This product was dissolved without purification in 1.0 ml of dry DMF.While stirring the solution at -10°60 C., 145 μl of isobutylamine, 320μl of diphenylphosphorylazide (hereinafter referred to simply as DPPA)and 207 μl of triethylamine were added thereto. The mixture was stirredat -10° C. for one hour and further at room temperature overnight. Then,60 ml of ethyl acetate was added to the reaction solution. The organiclayer was washed sequentially with a 10% citric acid aqueous solution,with water, with a 4% sodium hydrogencarbonate aqueous solution, withwater and with a Saturated Sodium chloride aqueous solution and thendried over anhydrous sodium sulfate. The solvent was distilled off underreduced Pressure, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate to obtain 204 mg of3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2(Z)-propenoicacid isobutylamide, 151 mg of 3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2(E)-propenoic acidisobutylamide and 55 ma of a mixture of both as colorless oilysubstances.

Rf:

2(Z) isomer: 0.37 (n-hexane/ethyl acetate=5/2)

2(E) isomer: 0.28 (n-hexane/ethyl acetate=5/2)

NMR (60 MHz, CDCl₃)

2(Z) isomer: δppm: 0.7-1.3(15H,m), 1.4-2.1(10H,m) 2.30(2H,M),3.20(2H,dd,J=6,6Hz) 3.8(1H,m), 4.52(1H,dd,J=2,9Hz) 5.12(2H,S),5.60(1H,br d,J=9Hz) 6.50(1H,m), 7.30(5H,s)

2(E) isomer: δppm: 0.7-1.3(15H,M), 1.3-2.0(10H,m) 2.30(2H,m),3.10(2H,dd,J=6,6Hz) 3.75(1H,M), 4.52(1H,dd,J=2,9Hz) 5.04(2H,s),5.75(1H,m), 6.00(1H,d,J=9Hz), 7.25(5H,s)

(c) 578 mg of3-[(4S,55)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2(Z,E)-propenoicacid isobutylamide was dissolved in 10 ml of methanol. A palladium blackcatalyst was added thereto, and hydrogen was continuously blown into itover a period of 4 hours. During the period, 0.2 ml of 1N hydrochloricacid was added seven times at intervals of about 30 minutes to maintainthe reaction solution to be weakly acidic. The catalyst was removed byfiltration, and the filtrate was concentrated under reduced pressure.The residue thereby obtained was dissolved in a solvent mixture ofdichloromethane/benzene and azeotropically concentrated under reducedpressure for drying. Then, similar drying was conducted under a solventmixture of dichloromethane/hexane to obtain 455 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide hydrochloride as white solid.

Rf: 0.52, 0.45 (chloroform/methanol/conc. aqueous ammonia=10/1/0.5)

(9) (2RS,4S,5S)-5-{L-N-[(2R orS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

20 mg of L-N-{(2R orS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl)norleucine tert-butylester was dissolved in 0.5 ml of dichloromethane. Then, 0.5 ml oftrifluoroacetic acid (hereinafter referred to simply as TFA) was addedthereto, and the mixture was reacted at room temperature for one hour.Then, the reaction solution was concentrated under reduced pressure, andthe resulting syrup was dissolved in benzene. This solution wasconcentrated under reduced pressure, and excess TFA was azeotropicallyevaporated and removed to finally obtain white solid. Obtained L-N-{(2Ror S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}norleucine wasthroughly dried under reduced pressure and dissolved in 0.3 ml of dryDMF. At a temperature of -20° C., 12 μl of triethylamine and 12 μl ofDPPA were successively added, and the mixture was stirred. Five minuteslater, 23 mg of (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide hydrochloride and 10 μl of triethylamine dissolved in0.4 ml of dry DMF were added to the previous reaction solution.

The mixture was stirred at -20° C. for one hour and at 5° C. overnightand then at room temperature for 3 hours. Then, the reaction solutionwas diluted with 20 ml of ethyl acetate and washed sequentially with 10ml of a 5% potassium hydrogen sulfate aqueous solution, with 10 ml of a4% sodium hydrogen carbonate aqueous solution and with 10 ml of asaturated sodium chloride aqueous solution. The separated ethyl acetatelayer was dried over anhydrous magnesium sulfate. The inorganic salt wasremoved by filtration, and the filtrate was concentrated under reducedpressure. The residue thereby obtained was purified by silica gel columnchromatography (chloroform/methanol=40/1). The eluted fractions of thedesired product were collected and concentrated, and the resulting syrupwas azeotropically concentrated under an ethyl ether solution to drynessto obtain 23 mg of the above identified compound as white solid.

Rf: 0.65 (chloroform/methanol 10/1)

EXAMPLE 2 (2RS,4S,5S)-5-{L-N-[(2R orS)-3-(pyrimidin-2-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) L-N-{(2R orS)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester

52 mg of L-N-{(2R orS)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl}norleucinetert-butyl ester obtained in Example 1 was dissolved in 0.5 ml of dryDMF. Separately, a suspension of a thioalkoxide (in 5 ml of dry DMF,prepared from about 80 mg of sodium hydride and 600 mg of2-mercaptopyrimidine, and 0.5 ml of the suspension was added to theabove reaction solution. The mixture was reacted at room temperature for4 hours. Then, 1 ml of water was added, and the reaction solution wasfurther diluted with 20 ml of ethyl acetate. The reaction solution waswashed with water (10 ml×2 times) and then washed with a saturatedsodium chloride aqueous solution. The organic layer was separated, driedover anhydrous magnesium sulfate and then concentrated under reducedpressure. The syrup thereby obtained was purified by silica gel columnchromatography (n-hexane/ethyl acetate=3/1). The eluted fractionscontaining the desired product were collected, concentrated and dried toobtain 41 mg of L-N-{(2 R orS)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester as syrup.

Rf: 0.22 (n-hexane/ethyl acetate 3/1)

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7Hz), 1.00-1.35(4H,m),1.37(9H,s) 1.56(1H,m), 1.75(1H,m), 3.04(1H,m), 3.38(1H,dd,J=6,14Hz),3.48(2H,m), 4.36(1H,m), 6.13(1H,d,J=7.15Hz), 6.96(1H,t,J=5Hz),7.3-7.5(4H,m), 7.70(dd,J=1.5,7.5Hz), 7.83(1H,m) 8.12(1H,m),8.45(1H,d,J=4.5Hz)

(2) L-N-{(2R orS)-3-(pyrimidin-2-yl)sulfonyl-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester

38 mg of L-N-{(2R orS)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester was dissolved in 1 ml of methanol. To the solution,0.25 ml of a 30% hydrogen peroxide aqueous solution and 18 mg of sodiumtungstate dehydrate were added, and the mixture was reacted at roomtemperature overnight. The reaction solution was diluted with 20 ml ofethyl acetate and washed sequentially with 10 ml of water and asaturated sodium chloride aqueous solution (10 ml×2 times). The organiclayer was separated, dried over anhydrous magnesium sulfate, andconcentrated and dried under reduced pressure to obtain 29 mg of theabove identified compound as white powder.

Rf: 0.26 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃):

δppm: 0.86(3H,t,J=7Hz), 1.20-1.38(4H,m), 1.39(9H,s), 1.61(1H,m),1.74(1H,m), 3.26(1H,m), 3.2-3.3(3H,m), 3.50(1H,dd,J=8,14Hz),3.72(1H,dd,J=3,15Hz), 4.14(1H,dd,J=8,15Hz), 4.30(1H,q,J=6Hz),6.08(1H,d,J=8Hz), 7.3-7.4(3H,M), 7.5(2H,m), 7.71(1H,d,J=8Hz),7.82(1H,m), 7.97(1H,d,J=8Hz), 8.63(1H,d,J=4.5Hz),

IR (KBr, neat): νm⁻¹ : 3380, 2960, 2940, 1730, 1670, 1570, 1390, 1320,1160, 1120

(3) (2RS,4S,5S)-5-{L-N-[(2R orS)-3-(pyrimidin-2-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

27 mg of L-N-{(2R orS)-3-(pyrimidin-2-yl)sulfonyl-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester was dissolved in 0.5 ml of dichloromethane. Then, 0.5mi of TFA was added thereto, and the mixture was reacted at roomtemperature for 3 hours. Then, the reaction solution was concentratedunder reduced pressure and the syrup thereby obtained was dissolved inbenzene. The solution was concentrated under reduced pressure and excessTFA was azeotropically removed. The solution was finally evaporated todryness to obtain white solid. L-N-{(2R orS)-3-(pyrimidin-2-yl)sulfonyl-2-(1-naphthylmethyl)propionyl}norleucinethus obtained was throughly dried under reduced pressure and thendissolved in 0.4 ml of dry DMF. Then, 21 μl of triethylamine and 14 μlof DPPA were added sequentially at -20° C., and the mixture was stirred.Five minutes later, a solution prepared by adding 27 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide hydrochloride and 15 μl of triethylamine to 0.5 μl of dryDMF, was added to the previous reaction solution and the mixture wasstirred at =20° C. for one hour, at 5° C. overnight and then at roomtemperature for 3 hours. The reaction solution was diluted with 20 ml ofethyl acetate and washed sequentially with 10 ml of a 5% potassiumhydrogensulfate aqueous solution, 10 ml of a 4% sodium hydrogencarbonateaqueous solution and with 10 ml of a saturated sodium chloride aqueoussolution. The ethyl acetate layer was separated and dried over-anhydrousmagnesium sulfate. The inorganic salt was removed by filtration, and thefiltrate was concentrated under reduced pressure. The residue therebyobtained was purified by silica gel column chromatography(chloroform/methanol=40/1). The eluted fractions containing the desiredproduct were collected and concentrated. The syrup thereby obtained wasazeotropically concentrated with dichloromethane,/hexane and evaporatedto dryness to obtain 31 mg of the above identified compound as whitesolid.

Rf: 0.54 (chloroform/methanol=10/1)

NMR (300 MHz, CDCl₃): δppm: 2.20(0.5H,m), 2.30(0.5H,m), 3.0(1H,m),3.12(1H,m), 3.28(2H,m), 3.5(1H,br), 3.6(1H,br), 3.7(1H,dd,J=2,14Hz),3.8-3.9(1H,br), 4.0-4.1(1H,m), 4.22(1H,m), 5.85(1H,br), 6.2(1H,br),6.42(1H,br), 7.27-7.40(3H,m), 7.50(2H,m), 7.72(1H,d,J=8Hz), 7.83(1H,m),7.91(1H,m), 8.55(1H,t,J=4.5Hz)

IR (KBr, neat): νcm⁻¹ : 3300, 2960, 2870, 1650, 1560, 1470, 139.0, 1320,1220, 1130

EXAMPLE 3 (2RS,4S,5S)-S-{L-N-[(2R orS)-3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionyl]-δ-hydroxynorvalyl}-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) 2,3-ethylenedioxybenzaldehyde

12.04 g of 2,3-dihydroxybenzaldehyde was dissolved in 120 ml of dry DMF.To this solution, 9.0 ml of 1.2-dibromoethane, 12.1 g of anhydrouspotassium carbonate and 1.1 g of cupric oxide were added. The reactionsolution was refluxed under heating for three hours on a hot water bathat 135° C. The reaction solution was diluted with 700 ml of benzene andthen washed with 500 ml of water. The aqueous layer was separated andextracted with benzene (500 ml×2 times). The extracted organic layerswere combined to the previously separated organic layer, the combinedorganic layer was dried over anhydrous magnesium sulfate. The inorganicsalt was removed by filtration, and the reaction solution wasconcentrated under reduced pressure to obtain a brown syrup. This syrupwas purified by silica gel column chromatography (n-hexane/acetone=5/1).The eluted solution was concentrated under reduced pressure, and theresidue was recrystallized from n-hexane/acetone to obtain 7.0 g of theabove identified compound as white crystals (melting point: 63°-64° C.)(yield: 49%). The mother solution was concentrated and dried to obtain3.2 g of the above identified compound as crude syrup (yield: 22%).

NMR (300 MHz, CDCl₃): δppm: 4.31(2H,m), 4.37(2H,m), 6.89(1H,t,J=8Hz),7.08(1H,dd,J=1,8HZ), 7.39(1H,dd,J=1,8Hz), 10.35(1H,s)

(2) 2,3-ethylenedioxybenzyl alcohol

3.15 g of 2,3-ethylenedioxybenzaldehyde was dissolved in 50 ml ofethanol. Then, 1.17 g of sodium borohydride was added thereto, and themixture was stirred at room temperature for one hour. The reactionsolution was concentrated under reduced pressure and then suspended withan addition of 100 ml of ethyl acetate. The suspension was washed with100 ml of water and then with 100 ml of saturated sodium chlorideaqueous solution. The separated ethyl acetate layer was dried overanhydrous magnesium sulfate. The inorganic salt was removed byfiltration, and the filtrate was concentrated under reduced pressure andthen purified by silica gel column chromatography (n-hexane/ethylacetate=2/1) to obtain 1.78 g of the above identified compound as whitesolid.

Rf: 0.2 (n-hexane/ethyl acetate=2/1)

(3) 2,3-ethylenedioxybenzyl chloride

4.3 g of 2,3-ethylenedioxybenzyl alcohol was dissolved in 50 ml of drydichloromethane. Then,, 2.1 ml of dry pyridine was dropwise addedthereto, and 3.8 ml of thionyl chloride was gradually added undercooling. The reaction solution was returned to room temperature and thenthe reaction solution was refluxed for 3 hours on a hot water bath at60° C. The reaction solution was concentrated under reduced pressure toobtain a syrup, which was then dissolved in 300 ml of ethyl acetate. Thesolution was washed with 200 ml of 0.1N hydrochloric acid and then twicewith 200 ml of a saturated sodium chloride aqueous solution. Then, thesolution was dried over anhydrous magnesium sulfate. The inorganic saltwas removed by filtration, and the filtrate was concentrated underreduced pressure and purified by silica gel column chromatography(n-hexane,/ethyl acetate=60/1) to obtain 4.0 g of the above identifiedcompound as syrup.

Rf: 0.64 (n-hexane//ethyl acetate=2/1)

(4) Diethyl (2,3-ethylenedioxybenzyl)malonate

Diethyl (2,3-ethylenedioxybenzyl)malonate was obtained from2,3-ethylenedioxybenzyl chloride and diethyl malonate in the same manneras the preparation of diethyl (1-naphthylmethyl)malonate.

NMR (300 MHz, CDCl₃): δppm: 1.21(3H,t,J=7Hz), 3.17(2H,d,J=8Hz)3.82(2H,d,J=8Hz), 4.15(4H,m), 4.26(4H,m), 6.72(3H,m)

IR (KBr):

νcm⁻¹ : 2990, 2940, 2880, 1740, 1610, 1480, 1370

(5) Ethyl (2,3-ethylenedioxybenzyl)malonate

Ethyl (2,3-ethylenedioxybenzyl)malonate was prepared from the product of(4) in the same manner as in the preparation of ethyl(1-naphthylmethyl)malonate.

NMR (300 MHz, CDCl₃): δppm: 1.20(3H,t,J=7Hz), 3.20(2H,m),3.85(1H,t,J=7.5Hz), 4.15(2H,m), 4.24(4H,m), 6.72(3H,m)

IR (KBr):

νcm⁻¹ : 2990, 2940, 2880, 1740, 1610, 1480

(6) Tert-butyl (2,3-ethylenedioxybenzyl)malonate

846 ml of ethyl (2,3-ethylenedioxybenzyl)malonate was dissolved in 20 mlof dry dichloromethane. After an addition of 0.2 ml of conc. sulfuricacid, isobutene gas was blown into the reaction solution under coolingat -78° C. and collected. After about 20 ml of isobutene was collected,the reactor was sealed. The reactor was returned to room temperature andstirred overnight. Then, the reactor was opened, and isobutene wasremoved by evaporation at room temperature under atmospheric pressure.The reaction solution was added to a solution mixture comprising 100 mlof a 0.5M sodium carbonate aqueous solution and 150 ml ofdichloromethane, and the mixture was vigorously stirred. The organiclayer was separated, washed with 100 ml of a saturated sodium chlorideaqueous solution and then dried over anhydrous magnesium sulfate. Theinorganic salt was removed by filtration, and the filtrate wasconcentrated under reduced pressure and purified by silica gel columnchromatography (n-hexane/ethyl acetate=4/1) to obtain 765 mg (yield:75%) of the above identified compound as colorless transparent syrup.

NMR (300 MHz, CDCl₃): δppm: 1.23(3H,t,J=7Hz), 1.39(9H,S),3.13(2H,d,J=8Hz), 3.74(1H,t,J=8Hz), 4.15(2H,m), 4.25(4H,m), 6.72(3H,m)

IR (KBr):

νcm⁻¹ : 2990, 1730, 1480, 1370, 1310, 1280

(7) Tert-butyl 2-(2,3-ethylenedioxybenzyl)-3-hydroxypropionate

761 mg of tert-butyl (2,3-ethylenedioxybenzyl)malonate was dissolved in20 ml of ethanol. Then, 0.57 g of sodium borohydride was added thereto,and the mixture was stirred at room temperature overnight. The reactionsolution was diluted with 150 ml of ethyl acetate and washed with 100 mlof water and then with 100 ml of a saturated sodium chloride aqueoussolution. The organic layer was dried over anhydrous magnesium sulfate,then concentrated under reduced pressure and purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=3/1) to obtain 241 mg(yield: 364) of the desired product as syrup.

NMR (300 MHz, CDCl₃): δppm: 1.41(9H,s), 2.39(1H,t,J=6.5Hz), 2.88(3H,m),3.70(2H,m), 4.25(4H,m), 6.73(3H,m)

IR (KBr):

νcm⁻¹ : 3480, 2980, 2930, 2880, 1730, 1610, 1480, 1370

(8) Tert-butyl2-(2,3-ethylenedioxybenzyl)-3-p-toluenesulfonyloxypropionate

238 mg of tert-butyl 2-(2,3-ethylenedioxybenzyl)-3-hydroxypropionate wasdissolved in 4 ml of dry pyridine, and 170 mg of p-toluenesulfonylchloride was added thereto. The mixture was reacted at room temperatureovernight and then concentrated under reduced pressure. The residue wasdissolved in 50 ml of ethyl acetate and washed sequentially with 50 mlof a 5% potassium hydrogensulfate aqueous solution, with 50 ml of a 4%sodium hydrogencarbonate aqueous solution and with 50 ml of a saturatedsodium chloride aqueous solution. The organic layer was dried overanhydrous magnesium sulfate, then concentrated under reduced pressureand purified by silica gel column chromatography (n-hexane/ethylacetate=3/1) to obtain 257 mg of tert-butyl2-(2,3-ethylenedioxybenzyl)-3-p-toluenesulfonyloxypropionate ascolorless transparent syrup.

NMR (300 MHz, CDCl₃): δppm: 1.32(9H,s), 2.45(3H,s), 2.78(2H,m),3.02(1H,m), 4.11(2H,m), 4.22(4H,m), 6.55(1H,dd,J=8,1Hz),6.68(1H,t,J=8Hz), 6.74(1H,dd,J=8,1Hz), 7.32(2H,d,J=8Hz),7.75(2H,d,J=8Hz)

(9) Tert-butyl 3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionate

87 mg of the tosyl compound obtained in the above step (8) was dissolvedin 0.5 ml of dry DMF, and a suspension comprising 27 mg of sodiumhydride, 65 μl of ethylmercaptan and 0.5 ml of dry DMF was addedthereto. The mixture was stirred at room temperature for one hour, andthen 1 ml of water was added to the reaction solution. After an addtionof 20 ml of benzene, the reaction solution was washed sequentially withwater (10 ml×2 times) and with 10 ml of a saturated sodium chlorideaqueous solution. The organic layer was dried over anhydrous magnesiumsulfate and concentrated under reduced pressure to obtain 58 mg of asyrup. Then, the syrup was dissolved in 2.5 ml of methanol, and 0.25 mlof a 30% hydrogen peroxide aqueous solution and 14 mg of sodiumtungstate dehydrate were added thereto. The mixture was stirredvigorously at room temperature for one hour. The reaction solution wasdiluted with 20 ml of benzene and washed with 10 ml of water and then 10ml of a saturated sodium chloride aqueous solution. The organic layerwas dried over anhydrous magnesium sulfate and then concentrated underreduced pressure to obtain 57 mg (yield: 79%) of the syrup of the aboveidentified compound.

NMR (300 MHz, CDCl₃): δppm: 1.33(3H,t,J=8Hz), 1.37(9H,s), 2.8-3.0(5H,m),3.39(1H,m), 3.55(1H,dd,J=14,10Hz), 4.28(4H,m), 6.65(dd,J=8,1Hz),6.76(1H,t,J=8Hz) 6.79(1H,dd,J=8,1Hz)

(10)L-0-acetyl-N-[3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionyl]-.delta.-hydroxynorvalinetert-butyl ester

Tert-butyl 3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionate wasdissolved in 1.2 ml of a dichloromethane/TFA (1/1) solution. Thesolution was stirred at room temperature for 3 hours and thenconcentrated under reduced pressure. The residue was dissolved inbenzene, and the benzene solution was concentrated under reducedpressure and azeotropically dried. The syrup thereby obtained wassubjected to condensation reaction with L-O-acetyl-δ-hydroxynorvalinetert-butyl ester by using a DPPA method (18 μl of triethylamine, 12 μlof DPPA and 2 ml of dry DMF), and the reaction mixture was purified bysilica gel column chromatography to obtain 26 mg (yield: 34%) of adiastereomer of a polar component and 36 mg (yield: 47%) of adiastereomer of a less-polar component, respectively, as syrups.

Polar component

NMR: δppm: 1.32-(3H,t,J=8Hz), 1.45(9H,s), 2.05(3H,s),2.78(1H,dd,J=14,9Hz), 2.85-3.0(4H,m), 3.26(1H,m), 3.67(1H,dd,J=14,10Hz),4.05(2H,t,J=7Hz), 4.2-4.4(5H,m), 6.29(1H,d,J=8Hz), 6.6(1H,dd,J=8,1Hz),6.72(1H,t,J=8Hz), 6.77(1H,dd,J=8,1Hz)

IR (KBr): νcm⁻¹ : 3370, 2980, 2940, 1740, 1680, 1540, 1480, 1460, 1400,1370

Less-polar component

NMR: δppm: 1.32(3H,t,J=8Hz), 1.45(9H,s), 2.05(3H,s), 2.8-3.0(5H,m),3.30(1H,m), 3.67(1H,dd,J=14,10Hz), 3.93(2H,t,J=6.5Hz), 4.25-4.4(5H,m),6.26(1H,d,J=8Hz), 6.62(1H,dd,J=8,1Hz), 6.73(1H,t,J=8Hz),6.78(1H,dd,J=8,1Hz)

IR (KBr): νcm⁻¹ : 3360, 2980, 2940, 1740, 1680, 1540, 1480, 1460, 1400,1370

(11)(2RS,4S,5S)-5-{L-N-[-3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionyl]-δ-hydroxynorvalyl)-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

34 mg of the less-polar component obtained in the above step (10) wassubjected to ester-removal in a solution mixture of dichloromethane/TFAin a usual method and then condensed with 24 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide by a DPPA method. The product was purified by columnchromatography to obtain 50 mg of a condensed product, which wasdissolved in 1.5 ml of ethanol/water (10/1), and 0.8 ml of a 2Npotassium hydroxide solution (ethanol/water=10/1) was added fordeacetylation. One hour later, the reaction solution was neutralized andextracted with ethyl acetate. The extract was washed with a saturatedsodium chloride aqueous solution and purified by silica gel columnchromatography and dried to obtain 23 mg of the above identifiedcompound as white solid.

Rf: 0.33 (chloroform/methanol=10/1)

(12) (2RS,4S,5S)-{(L-N-[(2S orR)-3-ethylsulfonyl-2-(2,3-ethylenedioxybenzyl)propionyl]-δ-hydroxynorvalyl}-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

24 mg of the polar component obtained in the above step (10) was treatedin the same manner as in step (11) to obtain 10 mg of the aboveidentified compound as 3 stereoisomer of the compound obtained in step(11).

Rf: 0.33 (chloroform/methanol=10/1)

EXAMPLE 4 (2S,4S,5S)-5-{L-N-((2R orS)-3-(1-methyltetrazol-5-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl)amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(a) 40 mg of L-N-[(2R orS)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl]norleucinetert-butyl ester obtained in Example 1-(5) was dissolved in 0.5.ml ofdry DMF. Then, 20 mg of 1-methyl-5-mercaptotetrazol sodium was addedthereto, and the mixture was reacted at room temperature overnight. Thereaction solution was diluted with 15 ml of ethyl acetate and washedwith water (10 ml) and a saturated sodium chloride aqueous solution (10ml×2 times). The organic layer was separated, dried over anhydroussodium sulfate and then concentrated under reduced pressure to 36 mg ofL-N-[(2R orS)-3-(1-methyltetrazol-5-yl)thio-2-(1-naphthylmethyl)propionyl]-norleucinetert-butyl ester as syrup.

Rf: 0.79 (n-hexane/ethyl acetate=1/1)

(b) 36 mg of L-N-[(2R orS)-3-(1-methyltetrazol-5-yl)thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 1.2 ml of methanol. Then, 0.3 ml of a30% hydrogen peroxide aqueous solution and 20 mg of sodium tungstatedehydrate were added thereto. The reaction solution was stirred at roomtemperature for two hours. Then, the reaction solution was diluted with15 ml of ethyl acetate and then washed sequentially with 10 ml of waterand with 10 ml of a saturated sodium chloride aqueous solution. Theorganic layer was separated and dried over anhydrous magnesium sulfate.The inorganic salt was removed by filtration, and the filtrate wasconcentrated under reduced pressure to obtain 34 mg of L-N-[(2R orS)-3-(1-methyltetrazol-5-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester as syrup.

Rf: 0.70 (n-hexane/ethyl acetate

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7Hz), 1.02-1.40(13H,m),1.55(1H,m), 1.70(1H,M), 3.35(1H,m), 3.45(2H,m), 3.74(1H,dd,J=3,15Hz),4.17(1H,m), 4.24(3H,s), 4.33(1H,dd,J=8,15Hz), 5.81(1H,d,J=8Hz),7.30(1H,d,J=8Hz), 7.38(1H,t,J=8Hz), 7.55(2H,m), 7.76(1H,d,J=8Hz),7.87(1H,d,J=8Hz), 8.01(1H,d,J=8Hz)

IR (KBr, neat): νcm⁻¹ : 3350, 2970, 2940, 2870, 1740, 1670, 1530, 146011400, 1370, 1350, 1250, 1220, 1140

(c) 32 mg of L-N-[(2R orS)-3-(1-methyltetrazol-5-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 0.7 ml of dichloromethane. Then, 0.5ml of TFA was added thereto, and the mixture was reacted at roomtemperature for one hour. Then, the reaction solution was concentratedunder reduced pressure. The syrup thereby obtained was sequentiallydissolved in benzene and benzene/n-hexane and then subjected toazeotropic concentration under reduced pressure to obtain a slightlyyellow powder. L-N-[(2R orS)-3-(1-methyltetrazol-5-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinethus obtained was throughly dried under reduced pressure and thendissolved in 0.5 ml of dry DMF. Then, 21 μl of triethylamine and 17 μlof DPPA were sequentially added thereto at -20° C., and the mixture wasstirred. Five minutes later, a solution mixture comprising 22 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydorxy-7-methyloctanoic acidisobutylamide hydrochloride, 22 μl of triethylamine and 8:5 ml of dryDMF, was added to the reaction solution, and the mixture was stirred at-20° C. for one hour and at 5° C. overnight. The reaction solutionthereby obtained was diluted with 20 ml of ethyl acetate and washedsequentially with 10 ml of a 2% sodium hydrogencarbonate aqueoussolution and with 10 ml of a saturated sodium chloride aqueous solution.The ethyl acetate layer was separated and dried over anhydrous sodiumsulfate. Then, the inorganic salt was removed by filtration, and thefiltrate was concentrated under reduced pressure. The residue therebyobtained was purified by silica gel column chromatography(chloroform/methanol=10/1). The eluted fractions containing the desiredproduct were collected and concentrated. The residue was reprecipitatedin an ethyl ether/pentane solution to obtain 33 mg of (2S,4S,5S)-5-(L-N-[(2R orS)-3-(1-methyltetrazol-5-yl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucil}-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide as white solid.

Rf: 0.64, 0.59 (chloroform/methanol 10/1)

NMR (300 MHz, CDCl₃): δppm: 2.18(0.5H,m), 2.29(0.5H,m), 3.03(1H,m),4.20(3H,s), 4.28(1H,m), 5.79(0.5H,br t), 5.83(0.5H,br t),5,98(0.5H,d,J=8Hz;, 6.02(0.5H,d,J=8Hz), 6.15(0.5H,d,J=8Hz),6.22(0.5H,d,J=8Hz), 7.31(1H,d,J=8Hz), 7.38(1H,t,J=8Hz), 7.55(2H,m),7.78(1H,d,J=8Hz), 7.87(1H,d,J=8Hz), 7.99(1H,d,J=8Hz)

IR (KBr): νcm⁻¹ : 3320, 2960, 1650, 1550, 1470, 1340, 1140

EXAMPLE 5(2RS,4S,5S)-S-{L-N-[(2S)-3-(1,3,4-thiadiazol-2-yl)thio-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1)L-N-{(2S)-3-(1,3,4-thiadiazol-2-yl)thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

37 mg ofL-N-((2R)-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl}norleucinetert-butyl ester was dissolved in 0.5 ml of dry DMF- Then, a solutioncomprising 21 mg of sodium hydride, 85 mg of 2-mercapto-1,3,4-thiadiazoland 0.8 ml of dry DMF was prepared and added to the above solution. Themixture was reacted at room temperature overnight. Then, the reactionsolution was diluted with 20 ml of ethyl acetate and washed sequentiallywith 20 ml of water and with 10 ml off a saturated sodium chlorideaqueous solution. The organic layer was separated, dried over anhydroussodium sulfate and then concentrated under reduced pressure. The residuewas purified by silica gel column chromatography (n-hexane/ethylacetate=2/1) to obtain 42 mg of the above identified compound as syrup.

NMR (300 MHz, CDCl₃): δppm: 0.84(3H,t,J=8.5Hz), 1.1-1.4(4H,m)1.4-1.8(2H,M), 3.24(1H,m), 3.4-3.5(2H,m), 3.69(2H,m), 7.34(2H,d,J=7Hz),7.46(2H,dt,J=7,1Hz), 7.53(2H,dt,J=7,1Hz), 7.70(1H,m),7.82(1H,dd,J=8,1Hz), 8.07(1H,dd,J=8,1Hz), 9.01(1H,s)

(2)(2RS,4S,5S)-5-{L-N-[(2S)-3-(1,3,4-thiadiazol-2-yl)thio-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

40 mg ofL-N-{(2S)-3-(1,3,4-thiadiazol-2-yl)thio-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester obtained in step (1) was deprotected in a solutionmixture comprising 0.5 ml of dichloromethane and 0.5 ml of TFA. Thereaction mixture was concentrated under reduced pressure, and theproduct was adsorbed on a resin of DEAE TOYO Pearl 650 mesh (OH⁻) by amethanol/water (10/1) solution and then eluted with a 0.2N acetic acidsolution (methanol/water=10/1). The eluted fractions containing thedesired product were collected and concentrated under reduced pressure.The residual syrup was dissolved in 10 ml of ethyl acetate and thenwashed with a saturated sodium chloride aqueous solution (8 ml×2 times).The organic layer was separated, dried over anhydrous sodium sulfate andconcentrated under reduced pressure to obtain 22 mg of solidL-N-[(2S)-3-(1,3,4-thiadiazol-2-yl)thio-2-(1-naphthylmethyl)propionyl]norleucine.This is condensed with(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide by a usual DPPA method. The product was purified by silicagel column chromatography (chloroform/methanol=40/1) to obtain 21 mg ofthe above identified compound.

Rf: 0.15 (Chloroform/methanol=30/1)

EXAMPLE 6(2RS,4S,5S)-5-(L-N-[(2S)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethylhydroxy-7-methyloctanoic acid isobutylamide

22 mg ofL-N-{(2S)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl}norleucinetert-butyl ester was dissolved in 1 ml of a dichloromethane/TFA (1/1)solution. Three hours later, the solution was concentrated under reducedpressure and then azeotropically concentrated with a benzene solutionand evaporated to dryness. The product is condensed by a DPPA method(triethylamine 18 μl, DPPA 12 μl,(2RS,4S,5S)-S-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide 18 mg, dry DMF 2 ml). The product was subjected to work upby a usual method and purified by silica gel column chromatography(chloroform/methanol 40/L) to obtain 24 mg of the above identifiedcompound as slightly yellow solid.

Rf: 0.33 (chloroform//methanol=50/1)

EXAMPLE 7(2RS,4S,5S)-5-{L-N-[(2S)-3-(pyrimidin-2-yl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1)L-N-{(2S)-3-(pyrimidin-2-yl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

29 mg ofL-N-{(2S)-3-(pyrimidin-2-yl)thio-2-(1-naphthylmethyl)propionyl)norleucinetert-butyl ester was dissolved in -a solution mixture comprising 1 ml ofmethanol and 0.1 ml of a 30% hydrogen peroxide aqueous solution. Then, 2mg of sodium tungstate dehydrate was added thereto, and the mixture wasstirred at room temperature for 3 hours. The reaction solution wasdiluted with 20 ml of ethyl acetate and washed with 10 ml of water andthen with 10 ml of a saturated sodium chloride aqueous solution. Theethyl acetate layer was separated, dried over anhydrous sodium sulfateand then concentrated under reduced pressure. The residue was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=1/1-1/2) toobtain 8 mg of above identified compound i.e. a sulfinyl compound inaddition to 12 mg of sulfone compound.

Rf: 0.14 (n-hexane/ethyl acetate=1//1)

NMR spectrum (300 MHz, CDCl₃): δppm: 0.83(1H,t,J=7.5Hz),0.39(2H,t,J=7.5Hz)

(2) (2RS, 4S, 5S)-5-{(L-N-[(2S)-3-(pyrimidin-2-yl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

8 mg of the compound obtained in step (1) was dissolved in 0.2 ml ofdichloromethane, and 0.35 ml of TFA was added thereto. After 1.5 hoursat room temperature, the mixture was concentrated under reducedpressure. The residue was dissolved in benzene/pentane solution andconcentrated under reduced pressure to dryness. The residue wasdissolved in 0.5 ml of dry DMF and cooled to -15° C., and then 5 μl oftriethylamine, 6 μl of DPPA and a solution in dry DMF (0.3 ml) of 7 mgof (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide and 4 μl of triethylamine, were sequentially added. Themixture was stirred at -15° C. for one hour and then at 5° C. overnight.Then, the mixture was diluted with 20 ml of ethyl acetate and washedsequentially with 10 ml of a 4% sodium hydrogen carbonate aqueoussolution with 10 ml of a saturated sodium chloride aqueous solution. Theorganic layer was separated, dried over anhydrous sodium sulfate andthen concentrated under reduced pressure. residue was purified by silicagel column chromatography (chloroform/methanol 30/1) to obtain 7.1 mg ofthe above identified compound.

Rf: 0.13, 0.17 (chloroform/methanol 30/1)

NMR (300 MHz, CDCl₃): δppm: 0.8-1.0(18H,m), 1.0-2.0(14H,m), 2.25(1H,m),3.8-4.3(11H)

EXAMPLE 8 (2R or S,4S,5S)-5-{L-N-[(2R orS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid 2-morpholinoethylamide

41.1 mg of L-N-(3-ethylsulfonyl-2-naphthylmethylpropionyl)norleucine wasdissolved in 0.25 ml of dry DMF. Then, 52 μl of triethylamine, 26 μl ofDPPA and 0.5 ml of a solution in dry DMF of 49 mg of(2RS,4S,5S)-S-amino-2-ethyl-4-hydroxyoctanoic acid2-morpholinoethylamide dihydrochloride were added thereto under stirringat -15° C. The mixture was stirred at room temperature overnight. Then,20 ml of ethyl acetate was added to the reaction solution, and themixture was washed with water and a saturated sodium chloride aqueoussolution. The organic layer was separated and dried over anhydrousmagnesium sulfate. Then, the solvent was distilled off under reducedpressure, and the residue was purified by silica gel columnchromatography (chloroform/methanol=30/1) to obtain 20.2 mg of the aboveidentified compound as white powder.

Rf: 0.10 (chloroform/methanol=30/1)

Mass spectrum m/z 731(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.83-1.02(12H,m), 1.19-1.94(14H,m),2.18-2.59(7H,m), 2.72-2.90(2H,m), 3.00(1H,d,J=14Hz), 3.25-3.92(12H,m),4.21(1H,ddd,J=4.7,13HZ), 6.05-6.20(2H,m) 6.28-6.35(1H,m),7.32-7.46(2H,m), 7.49-7.64(2H,m), 7.78(1H,d,J=8Hz), 7.88(1H,d,J=8Hz),8.03(1H,d,J=8Hz)

EXAMPLE 9(2RS,4S,5S)-5-(L-N-((2S)-3-ethylsulfonyl-2-(4-quinolylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) Ethyl 2-diethylphosohono-3-(4-quinolyl)propionate 1.2 g of sodiumhydride was suspended in 30 ml of dry DMF, and 5.9 ml of ethyldiethylphosphonoacetate was dropwise added thereto under cooling withice. The mixture was stirred at room temperature for one hour, and 12 mlof a solution in dry DMF of 5.31 g of (4-chloromethyl)quinoline wasadded under cooling with ice. Ten minutes later, the reaction solutionwas returned to room temperature and stirred overnight. Then, thereaction solution was acidified by an addition of 200 ml of 0.5Nhydrochloric acid and washed with 200 ml of ethyl acetate. The aqueouslayer was separated and made basic by an addition of about 20 g ofsodium hydrogen carbonate. The product was extracted with 300 ml ofethyl acetate. The ethyl acetate layer was washed with 200 ml of asaturated sodium chloride aqueous solution, dried over anhydrous sodiumsulfate and concentrated under reduced pressure. The residue waspurified by silica gel column chromatography (ethyl acetate) and driedunder reduced pressure to obtain 6.41 g (yield: 59%) of the aboveidentified compound as yellow syrup.

NMR (300 MHz, CDCl₃): δppm: 1.13(3H,t,J=7.0Hz), 1.38(3H,t,J=7.1Hz),1.40(3H,t,J=7.2Hz), 3.40(ddd,J=23.0,10.9,3.6Hz), 3.65(1H,M), 3.76(1H,m),4.10(2H,m), 4.24(4H,m), 7.27(1H,d,J=4.9HZ), 7.61(ddd,J=8.5,7.0,1.6Hz),7.73(ddd,J=8.3,6.9,1.5), 8.07(1H,dd,J=8.6,1.0), 8.12(1H,dd,J=8.6,1.0Hz),8.80(1H,d,J=4.4Hz)

(2) Ethyl 2-(4-quinolylmethyl)acrylate

140 mg of anhydrous lithium chloride was dissolved in 7 ml of dry THF,and 3 ml of a THF solution of 1.04 g of ethyl2-diethylphosphono-3-(4-quinolyl)propionate was added thereto. Then, 1.7ml of DBU/THF (12/25) was added, and then a 3 ml of a THF solution of0.14 g of paraformaldehyde was added thereto. The mixture was stirred atroom temperature for one hour, and then the insoluble materials wereremoved by filtration. The product collected by filtration was washedwith a small amount of benzene, and the washed solution was combinedwith the filtrate. The combined filtrate was diluted with 60 ml of ethylacetate and washed with 40 ml of water and then with 40 ml of asaturated sodium chloride aqueous solution. The organic layer wasseparated, dried over anhydrous sodium sulfate, concentrated and thenpurified by silica gel column chromatography (n-hexane/ethylacetate=3/1) to obtain 601 mg of the above identified compound as syrup.

NMR (300 MHz, CDCl₃): δppm: 1.29(3H,t,J=7.2Hz), 4.11(2H,s),4.24(2H,q,J=7.1Hz), 5.32(1H,s), 6.32(1H,s), 7.24(1H,d,J=4.3Hz),7.55(1H,ddd,J=8.3,6.8,1.5Hz), 7.71(1H,ddd,J=8.3,6.8,1.5Hz)7.97(1H,dd,J=8.7,1.6Hz), 8.13(1H,dd,J=7.9,0.7Hz), 8.84(1H,d,J=4.3Hz)

(3) 3-Ethylthio-2-(4-guinolylmethyl)propionic acid

597 mg of ethyl 2-(4-quinolylmethyl)acrylate was dissolved in 3 ml ofethylmercaptan. Then, 50 mg of potassium tert-butoxide was addedthereto, and the mixture was stirred at room temperature for two hours.Then, the reaction solution was diluted with 60 ml of ethyl acetate andwashed with 40 ml of water and then with 40 ml of saturated sodiumchloride aqueous solution. The organic layer was separated, dried overanhydrous magnesium sulfate and then concentrated under reducedpressure. The residual syrup was purified by silica gel columnchromatography (n-hexane/ethyl acetate=5,/2) and dried to obtain 640 mg(yield: 85%) of the desired product as syrup.

Rf: 0.47 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 1.10(3H,t,J=7.3Hz), 1.25(3H,t,J=7.3Hz),2.56(2H,q,J=7.5Hz), 2.74(1H,dd,J=13.0,7.0Hz;, 2.91(1H,dd,J=13.2,7.2Hz),3.04(1H,m), 3.39(1H,dd,J=13.9,8.5Hz), 3.51(1H,dd,J=13.9,5.9Hz),4.05(2H,m), 7.26(1H,d,J=4.4Hz), 7.59(1.5H,ddd,J=8.4,6.9Hz),7.72(ddd,J=8.3,6.9,1.4Hz), 8.09(1H,dd,J=8.7,1.4Hz),8.12(1H,dd,J=9.7,0.9Hz), 8.80(1H,d,J=4.4Hz)

Then, this product was saponified by using 12 ml of a 1N potassiumhydroxide in ethanol/water (10/1). The reaction mixture was left at roomtemperature for 3 hours and then concentrated at room temperature to avolume of from 2 to 3 ml. The mixture was diluted with 35 ml of waterand washed with 40 ml of ethyl ether. The aqueous layer was separatedand neutralized by an addition of about 10 ml of 1N hydrochloric acid,and then 5 g of sodium chloride was added thereto. The aqueous layer wasextracted four times with 40 ml of ethyl acetate/ethanol (10/1), and theextract was dried over anhydrous magnesium sulfate. The inorganic saltwas removed by filtration, and the filtrate was concentrated underreduced pressure to obtain 502 mg (yield: 54%) of the above identifiedcompound as white crystals.

Melting point: 168°-170° C.

(4) L-N-[(2R or S)-3-ethylthio-2-(4-guinolylmethyl)propionyl]norleucinetert-butyl ester

255 mg of 3-ethylthio-2-(4-quinolylmethyl)-propionic acid was subjectedto a condensation reaction with 0.19 ml (1.5 eq) of triethylamine, 0.26ml (1.3 eq) of DPPA and 248 mg of L-norleucine tert-butyl ester in 4 mlof dry DMF. The product was subjected to a usual after treatment and thepurified by silica gel column chromatography (n-hexane/ethylacetate=2/1) to obtain 189 mg (yield: 46%) of a diastereomer (polarcomponent) and 188 mg (yield: 46%) of a diastereomer (less-polarcomponent), respectively, as syrups.

NMR (300 MHz, CDCl₃)

Polar component: δppm: 2.54(2H,m), 2.72(2H,m), 2.93(1H,dd,J=L4.2,9.5Hz),3.41(2H,m), 4.34(1H,m), 5.89(1H,d,J=7.5Hz)

Less-polar component: δppm: 2.59(2H,q,J=7.0Hz), 2.71(1H,m),2.79(1H,dd,J=13.1,7.2), 2.97(1H,dd,J=12.8,6.9Hz),3.33(1H,dd,J=13.2.9.8Hz), 3.55(1H,dd,J=13.6,4.3HZ), 4.34(1H,m).5.74(1H,d,J=7.5Hz)

(5(2RS,4S,5S)-5-{L-N-[(2S)-3-ethylsulfonyl-2-(4-quinolylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

86 mg of L-N-[(2S)-3-ethylthio-2-(2-quinolylmethyl)propionyl]norleucineobtained as the polar component in step (4) was oxidized with a hydrogenperoxide aqueous solution/sodium tungstate in a usual manner to obtain88 mg ofL-N-[(2)-3-ethylsulphonyl-2-(4-quinolylmethyl)propyionyl]norleucinetert-butyl ester. This was deprotected with a dichloromethane/TFAsolution in a usual manner and condensed with(2SR,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamine by a usual DPPA method to obtain 39 mg of the aboveidentified compound.

Rf: 0.48 (chloroform/methanol=10/1)

EXAMPLE 10(2RS,4S,5S)-5-{L-N-[(2S)-3-ethylsulfonyl-2(8-quinolylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) -3-ethylthio-2-(8-quinolylmethyl)propionic acid

In the same manner as in Example 9 (1) to (3), the above identifiedcompound was obtained from ethyl2-diethylphosphono-3-(8-quinolyl)propionate by the Horner-Emmonsreaction with formalin, followed by the Micheal addition reaction withethylmercaptane and the saponification by means of potassium hydroxide.

Melting point: 143°-145° C.

NMR (300 MHz, CDCl₃): δppm: 1.16(3H,t,J=7.5HZ), 2.41(2H,M),2.83(1H,dd,J=9.1Hz), 2.96(1H,m), 3.15(1H,dd,J=5.4,12.4Hz),3.22(1H,dd,J=4.7,14.9Hz), 3.87(1H,dd,J=4.2,14.6Hz), 7.59(2H,m),7.83(2H,M), 8.38(1H,dd,J=1.1,8.5Hz), 8.92(1H,dd,J=1.7,4.7Hz)

(2) N-[3-ethylsulfonyl-2-(8-guinolylmethyl)propionylnorleucinetert-butyl ester

114 mg of 3-ethylthio-2-(8-quinolylmethyl)propionic acid obtained instep (1) was condensed with norleucine tert-butyl ester by a usual DPPAmethod. The product was purified by silica gel column chromatography toobtain 149 mg of a condensed product (yield: 81%). Then, it wassubjected to oxidation with a hydrogen peroxide aqueous solution/sodiumtungstate in a usual manner, and the product was separated and purifiedby silica gel column chromatography (n-hexane/ethyl acetate 1/1) toobtain 79 mg (yield: 50%) of a polar diastereoisomer and 68 mg (yield:43%) of a less-polar diastereoisomer, respectively, as syrups.

NMR

Less-polar component: δppm: 2.83-3.03(3H,m), 3.22(1H,dd,J=7.3,13.0Hz),3.60(1H,m), 3.71(1H,m), 3.87(1H,dd,J=9.7,14.5Hz), 4.32(1H,m)

Polar component: δppm: 2.8-3.0(3H,m), 3.G8(1H,dd,J=8.7,13.2Hz),3.53(1H,br), 3.88(dd,J=10.2,14.7Hz), 3.91(1H,m), 4.42(1H,m)

(3)(2RS,4S,5S)-5-{L-N-[(2S)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

19 mg of the polar diastereoisomer obtained in step (2) was dissolved-in0.5 ml of dichloromethane and 0.7 ml of TFA, and the solution wasreacted at room temperature for 5 hours. Then, the reaction mixture wasconcentrated under reduced pressure. The residue thereby obtained wasdissolved in dichloromethane, benzene and n-pentane and concentratedunder reduced pressure and azeotropically dried to obtain 21 mg of asolid. This product was condensed with(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide by a usual DPPA method. The product was purified by silicagel column chromatography (chloroform/methanol=30/l) to obtain 10 mg ofthe above identified compound as solid.

Rf: 0.54 (chloroform/methanol=10/1)

(4)(2RS,4S,5S)-5-{L-N-[(2R)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoic-acidisobutylamide

21 mg of the less-polar diastereoisomer obtained in step (2) was treatedin the same manner as in step (3), and after the tert-butyl group wasdeprotected, subjected to the condensation reaction by a DPPA method.The product was purified by silica gel column chromatography to obtain15 mg of the above identified compound as white solid,, which is thestereo isomer of the compound obtained in step (3).

Rf: 0.49 (chloroform/methanol 10/1)

EXAMPLE 11

(2RS,4S,5S)-5-{L-Nα-[2(S)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]histidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide (1) L-N.sup.α -tert-butoxycarbonyl-N^(im)-triphenylmethyl-histidine methyl ester

1.43 9 of L-N.sup.α -tert-butoxycarbonylhistidine methyl ester wasdissolved in 15 ml of dry dichloromethane. Then, 1.8 g oftriphenylmethyl chloride was added thereto. and 0.18 ml of triethylaminewas further added thereto, The mixture wa5 stirred at room temperaturefor 30 minutes, and the reaction solution was diluted with 150 ml ofchlorolorm. The reaction solution was washed with 100 ml of water andthen dried over anhydrous sodium sulfate. The inorganic salt was removedby filtration, and the filtrate was concentrated under reduced pressureand prurified by silica gel column chromatography(chloroform/methanol=30/1) to obtain 2.6 g (yield: 89%) of the aboveidentified compound as white solid.

Rf: 0.31 (chloroform/methanol=30/1)

(2) L-N^(im) -triphenylmethylhistidine methyl ester

1.2 g of L-N.sup.α -tert-butoxycarbonyl-N^(im) -triphenylmethylhistidinemethyl ester was dissolved in 4 ml of dichloromethane. Then, 4 ml of TFAwas added thereto, and the mixture was left to stand at room temperaturefor 15 minutes and then immediately diluted by an addition of 50 ml ofbenzene. The mixture was quickly concentrated under reduced pressure.The residue was concentrated under reduced pressure in thebenzene/hexane solution and was azeotropically removed excess TFA. Theresidue was dissolved in 100 ml of ethyl acetate and washed sequentiallywith 100 ml of a 4% sodium hydrogen carbonate aqueous solution and with100 ml of a saturated sodium chloride aqueous solution. The organiclayer was dried over anhydrous sodium sulfate. The reaction solution wasconcentrated under reduced pressure, and the residue was purified bysilica gel column chromatography (chloroform/methanol/conc. aqueousammonia=400/15/0.4. The eluted fractions containing the desired productwere collected and dried over anhydrous magnesium sulfate. The inorganicsalt was removed bu filtration, and the filtrate was concentrated underreduced pressure to obtain 474 mg (yield: 49%) of the desired product aswhite solid.

Rf: 0.59 (chloroform/methanol/conc. aqueous ammonia 10/0.5/0.2)

NMR (300 MHz, CDCl₃): δppm: 2.87(1H,dd,J=14,7Hz), 2.99(1H,dd,J=14,6Hz),6.59(1H,s), 7.12(6H,m), 7.33(9H,m), 7.37(1H,s)

(3) L-N.sup.α -[3-ethylthio-2-(8-guinolylmethyl)propionyl]-N^(im)-triphenylmethylhistidine methyl ester

69 mg of 3-ethylthio-2-(8-quinolylmethyl)propionic acid obtained inExample 10 (1) and 113 mg of L-N^(im) -triphenylmethylhistidine methylester obtained in step (2) of this Example were condensed by a DPPAmethod (52 μl of triethylamine, 65 μl of DPPA and 2.6 ml of dry DMF).The product was purified by silica gel column chromatography(benzene/methanol=25/1) to obtain 64 mg of hygroscopic solid as amixture of diastereomers.

NMR (300 MHz, CDCl₃): δppm: 1.08(3H,tx2,J=7.5Hz), 3.58,3.66(3H,sx2)

(4) L-N.sup.α -(2(R orS)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]-N^(im)-triphenylmethylhistidine

61 mg of L-N.sup.α -(3-ethylthio-2-(8-quinolylmethyl)-propionyl]-N^(im)-triphenylmethylhistidine methyl ester obtained in the preceeding stepwas dissolved in 1 ml cf methanol. Then, 1 ml of a 2N potassiumhydroxide solution (methanol/water=10/1) was added thereto, and themixture was stirred at room temperature for 1.5 hours. Then, thereaction solution was neutralized with 1N hydrochloric acid undercooling with ice. The reaction solution was diluted with 10 ml of asaturated sodium chloride aqueous solution and extracted with ethylacetate (29 ml×2 times), and the extract was concentrated under reducedpressure. The residue was dissolved in 2.2 ml of methanol/30% hydrogenperoxide aqueous solution (10/1). Then, 4 mg of sodium tungstatedehydrate was added thereto, and the mixture was stirred for two hours.The reaction solution was diluted with 20 ml of ethyl acetate and washedwith 10 ml of a saturated sodium chloride aqueous solution. The organiclayer was dried over anhydrous magnesium sulfate and evaporated underreduced pressure to dryness to obtain 53 mg of the above identifiedcompound as yellow solid.

Rf: 0.28, 0.36 (chloroform/methanol/33% acetic acid 10/1/0.5)

(5) (2SR,4S,5S)-5-{L-N.sup.α -[2(R orS)-3-ethylsulfonyl-2-(8-guinolylmethyl)propionyl]histidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

53 mg of L-N.sup.α -[2(R orS)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]-N^(im)-triphenylmethylhistidine obtained by the preceeding step was condensedwith 30 mg of (29R,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide by a DPPA method (20 μl of triethylamine and 0.8 mlof DPPA). The product was subjected to work up in a usual manner andpurified by silica gel column chromatography to obtain 63 mg of yellowsolid. This product was dissolved in 1.0 ml of dichloromethane, and 0.5ml of TFA was added to remove the protective group for the trityl group.The product was concentrated and dried under reduced pressure, and thenstereoisomers of the above identified compound were separated by meansof preparative TLC (Merck Art. 5715) to obtain 14.3 mg of a polarcomponent (identified as the titled compound) and 9.4 mg of a less-polarcomponent.

Rf: (benzene/methanol=10/1)

Polar, component: 0.16

Less-polar component: 0.20

EXAMPLE 12 2RS,4S,5S)-S-{L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) Ethyl 2-diethylphosphono-5-(2-tetrahydropyranyloxy)pentanoate

0.58 ml of 3-bromo-1-propanol was dissolved in 6 ml of drydichloromethane, and 1.112 ml of dihydropyrane and 10 mg of dryp-toluenesulfonic acid were added thereto. The mixture was stirred atroom temperature overnight. The reaction solution was separated with 30ml. of chloroform and 15 ml of a 4% sodium hydrogencarbonate aqueoussolution. The organic layer was washed with water and dried overanhydrous magnesium sulfate, and the solvent was distilled off underreduced pressure. The residue was separated by silica gel columnchromatography (chloroform). Then, the fraction containing the productwas purified by silica gel column chromatography (n-hexane/ethylacetate=20/1). The combined fraction containing the product wassubjected to the removal of the solvent under reduced pressure to obtain1.44 g of 3-bromo-l-(2-tetrahydropyranyloxy)propane as colorless oilysubstance.

Rf: 0.33 (n-hexane/ethyl acetate=10/1)

215 mg of sodium hydride (50% in oil) was washed three times withn-hexane under argon atmosphere to separate the oil. The powder obtainedafter drying was suspended in 1.5 ml of dry DMF under an argon stream,and the suspension was cooled to 0° C. Then, to this mixture, 0.9 ml ofethyl diethylphosphonoacetate was dropwise added over a period of onehour. The mixture was stirred at room temperature for 30 minutes andcooled to 0° C. Then 1.23 g of 3-bromo-1-(2-tetrahydropyranyloxy)propanewas added thereto. The mixture was stirred at room temperature overnightand at 65° C. for 8 hours. The mixture was poured into 15 ml of waterand extracted three times with 20 ml of chloroform. The organic solventlayer was washed with water and dried over anhydrous magnesium, sulfate.The solvent was distilled off under reduced pressure. The residue wasseparated by silica gel column chromatography (n-hexane/ethylacetate=2//1). The fraction containing the product was again purified bysilica gel column chromatography to obtain 583 mg of ethyl2-diethylphosphono-5-(2-tetrahydropyranyloxy)pentanoate as colorlessoily substance.

Mass spectrum m/z 367(M⁺ +1)

Rf: 0.33 (n-hexane/ethyl acetate=1/5)

(2) Ethyl(2RS)-(1-naphthylmethyl)-5-(2-tetrahydropyranyloxy)-2-pentanoate

(a) 579 mg of lithium chloride was suspended in 20 mi of dry THF underan argon stream, and 5.0 g of ethyl2-diethylphosphono-5-(2-tetrahydropyranyloxy)pentanoate was added understirring. After stirring the mixture for 5 minutes at room temperature,2.6 g of DBU was added, and the mixture was stirred at room temperaturefor 10 minutes. Then,, 1.7 g of α-naphthoaldehyde was added, and themixture was stirred at room temperature overnight. Then, the reactionsolution was neutralized with 1N hydrochloric acid under cooling withice and extracted with ethyl acetate. The ethyl acetate layer therebyobtained was washed with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. The solventwas distilled off under reduced pressure, and the residue was purifiedby silica gel column chromatography (n-hexane,/ethyl acetate 10/1) toobtain 3.37 g of ethyl3-(1-naphthyl)-2-[3-(2-tetrahydropyranyloxy)propyl]-2-propenoate asslightly yellow oily substance.

Rf: 0.15 (n-hexane/ethyl acetate=10/1)

NMR (300 MHz, CDCl₃): δppm: 1.20-1.52(8H), 1.65(1H,m), 1.78(2H,m),2.51(2H,m), 3.25(1H,m), 3.33(1H,m), 3.57-3.74(2H,m), 4.27(1H,m),4.35(2H,q,J=7Hz), 7.36-7.56(4H), 7.78-7.95(3H), 8.18(1H,s)

(b) 3.37 g of ethyl3-(1-naphthyl)-2-[3-(2-tetrahydropyranyloxy)propyl]-2-propenoate wasdissolved in 5 ml of ethanol and hydrogenated under atmospheric pressureby means of 10% palladium carbon. The reaction, mixture was subjected tofiltration, the solvent of the filtrate was distilled off under reducedpressure to obtain 3.36 g of ethyl(2RS)-2-(1-naphthylmethyl)-5-(2-tetrahydropyranyloxy)pentanoate as oilysubstance.

Rf: 0.18 (n-hexane/ethyl acetate=10/1)

NMR (300 MHz, CDCl₃): δppm: 1.10(3H,t,J=7.5Hz), 1.42-1.91(10H),2.89(1H,m), 3.22(1H,m), 3.29-3.50(3H), 3.64-3.84(2H,m),4.04(2H,q,J=7.5Hz), 4.52(1H,m), 7.35(2H,m), 7.50(2H,m),7.73(1H,d,J=8Hz), 7.85(1H,d,J=8Hz), 8.03(1H,d,J=8Hz)

(3) (2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoic acid

(a) 3.36 g of ethyl(2RS)-2-(1-naphthylmethyl)-5-(2-tetrahydropyranyloxy)pentanoate wasdissolved in 19 ml of methanol. Then, 3 ml of 1N hydrochloric acid wasadded, and the mixture was stirred at room temperature for two hours.The reaction solution was neutralized with a saturated sodiumhydrogencarbonate aqueous solution under cooling with ice, and thesolvent was distilled off under reduced pressure. To the residue, 15 mlof water was added, and the mixture was extracted with ethyl acetate.The ethyl acetate layer was washed with water and with a saturatedsodium chloride aqueous solution and then dried over anhydrous sodiumsulfate. On the other hand, the separated aqueous layer was adjusted topH2 with 1N hydrochloric acid under cooling with ice and then extractedwith ethyl acetate. This ethyl acetate layer was also washed with waterand with a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The organic layers were put together, and thesolvent was distilled off under reduced pressure to obtain 2.31 g of amixture of the ethyl ester and methyl ester of(2RS)-5-hydroxy-2-(1-naphthylmethyl)pentanoic acid was obtained ascolorless oily substance.

Rf: 0.40, 0.44 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 1.10(3Hx0.5,t,J=7.1 Hz), 1.48-1.90(8H),2.89(1H,m), 3.20(1H,m) 3.42(1H,m), 3.58(3Hx0.5,s), 3.61(2H,t,J=7.9 Hz),4.03(2Hx0.5,q,J=7.1 Hz), 7.27-7.40(2H,m), 7.44-7.58(2H), 7.73(1H,d,J=7.9Hz), 7.86(1H,d,J=7.9 Hz), 8.01(1H,d,J=7.9 Hz)

(b) 2.31 g of the mixture of the ethyl ester and methyl ester of(2RS)-5-hydroxy-2-(1-naphthylmethyl)pentanoic acid was dissolved in 35ml of dry pyridine, and 1.69 g of p-toluenesulfonyl chloride was addedthereto. The mixture was stirred at room temperature overnight. Thereaction solution was concentrated under reduced pressure, and 200 ml ofethyl acetate was added to the residue. The ethyl acetate layer waswashed with a 5% potassium hydrogensulfate aqueous solution, with a 5%sodium hydrogencarbonate aqueous solution and with a saturated sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Thesolvent was distilled off under reduced pressure and the residue waspurified by silica gel column chromatography (n-hexane/ethylacetate=5/1) to obtain 643 mg of ethyl(2RS)-2-(1-naphthylmethyl)-5-p-toluenesulfonyloxypentanoate, 184 mg ofmethyl (2RS)-2-(1-naphthylmethyl)-5-p-toluenesulfonyloxypentanoate and650 mg of a mixture of the two compounds.

Ethyl ester

Rf: 0.37 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 1.07(3H,t,J=7.1 Hz), 1.52-1.80(4H)2.41(3H,s), 2.78(1H,m), 3.12(1H,m), 3.38(1H,m), 3.98(2H,m),4.01(2H,q,J=7.1 Hz) 7.20-7.40(4H), 7.44-7.57(2H), 7.74(3H),7.85(1H,d,J=7.9 Hz), 7.95(1H,d,J=7.9 Hz)

Methyl ester

Rf: 0.30 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃) δppm: 1.50-1.82(4H), 2.42(3H,s), 2.80(1H,m),3.12(1H,m), 3.40(1H,m), 3.54(3H,s), 3.95(2H,m), 7.20-7.31(4H),7.35-7.60(2H), 7.74(3H), 7.89(1H,d,J=7.9 Hz), 7.96(1H,d,J=7.9 Hz)

(c) 454 mg of sodium hydride (60% in oil) was washed three times withn-pentane under an argon stream to remove the oil. The powder obtainedafter drying was suspended in 10 ml of dry DMF under an argon stream,and 882 mg of ethylmercaptan was added thereto under stirring at 0° C.The mixture was stirred at room temperature for one hour. The suspensionthus prepared was added to a solution in dry DMF (10 ml) of 1.47 g ofthe mixture of the ethyl ester and methyl ester of(2RS)-2-(1-naphthylmethyl)-5-p-toluenesulfonyloxypentanoic acid understirring with ice. The mixture was stirred at room temperature for onehour. Then, 25 ml of water was added and then 200 ml of benzene wasadded to the reaction solution. The organic layer was separated, washedwith water and with a saturated sodium chloride aqueous solution anddried over anhydrous sodium sulfate. Then, the solvent was distilled offunder reduced pressure to obtain 1.2 g of a mixture of the ethyl esterand methyl ester of (2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoicacid.

Rf: 0.68, 0.63 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 1.19(3H,t,J=7.1 Hz), 1.29(3Hx0.5,t,J=7.1Hz), 1.45-1.68(3H), 1.80(1H,m), 2.45(3H,m), 2.66(1H,m), 2.82(1H,m),3.16(1H,m), 3.38(1H,m), 3.54(3Hx0.5,s), 3.98(2Hx0.5,q,J=7.1 Hz),7.22-7.36(2H), 7.40-7.53 (2H), 7.68(1H,d,J=7.9 Hz), 7.81(1H,d,J=7.9 Hz),7.97(1H,d,J=7.9 Hz)

(d) 1.2 g of the mixture of the ethyl ester and methyl ester of(2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoic acid was dissolved in 12ml of ethanol/water (10/1). Then, 9.3 ml of a solution of 2N potassiumhydroxide in ethanol/water (10/1) was dropwise added thereto understirring. The mixture was stirred at room temperature overnight. Then,the reaction solution was concentrated under reduced pressure to about 3ml, and then 40 ml of water was added thereto. The aqueous solution wasadjusted to pH2 by an addition of 1N hydrochloric acid under coolingwith ice and then extracted with ethyl acetate. The ethyl acetate layerwas washed with water and with a saturated sodium chloride aqueoussolution and then dried over anhydrous sodium sulfate. Then, the solventwas distilled off under reduced pressure to obtain 953 mg of(2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoic acid.

Rf: 0.42 (chloroform/methanol/acetetic acid=10/0.5/0.1)

NMR (300 MHz, CDCl₃): δppm: 1.22(3H,t,J=7.1 Hz), 1.49-1.91(4H)2.42-2.55(4H), 2.90(1H,m), 3.20(1H,m), 3.50(1H,m), 7.30-7.42(2H)7.45-7.58(2H), 7.75(1Hd,J=7.9 Hz) 7.88(1H,d,J=7.9 Hz), 8.02(1H,d,J=7.9Hz)

(4) L-N-[(2R or S)-5-ethylthio-2-(1-naphthylmethyl)pentanyl]norleucine

(a) 953 mg of (2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoic acid wasdissolved in 9 ml of dry DMF, and 649 mg of L-norleucine tert-butylester, 782 mg of 1-hydroxybenzotriazol and 904 mg of DCC were addedunder cooling with ice. The mixture was stirred at room temperatureovernight. The precipitated dicyclohexyl urea was removed by filtration,and the precipitates were washed with a small amount of a solventmixture of n-hexane/ethyl acetate (4/1). The washing solution wascombined to the filtrate. Then, 100 ml of ethyl acetate was added to thefiltrate, and the ethyl acetate layer was washed with a 10% citric acidaqueous solution, with water, with a 4% sodium hydrogencarbonate aqueoussolution, with water and with a saturated sodium chloride aqueoussolution and dried over anhydrous sodium sulfate. The solvent wasdistilled off under reduced pressure. To the residue, a small amount ofchloroform was added, and insolubles were removed by filtration. Then,the solvent in the filtrate was distilled off. The residue was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=7/1) toobtain 1.23 g ofL-N-[(2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucinetert-butyl ester. 610 mg thereof is further purified by silica gelcolumn chromatography (toluene/ethyl acetate=25/1) to obtain 280 mg ofL-N-[(2R or S)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucinetert-butyl ester having a high Rf value and 210 mg of L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine tert-butyl esterhaving a low Rf value.

(2R or S) isomer having a high Rf value

Rf: 0.53 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7.5 Hz), 1.06-1.32(7H)1.40(9H,s), 1.45-1.80(5H), 1.90(1H,m), 2.40-2.60(5H), 3.20(1H,m),3.36(1H,m), 4.33(1H,m), 5.72(1H,d,J=7.9 Hz), 7.21-7.40(2H),7.45-7.58(2H), 7.70(1H,d,J=7.9 Hz), 7.84(1H,d,J=7.9 Hz), 8.01(1H,d,J=7.9Hz)

(2S or R) isomer having a low Rf value

Rf: 0.49 (n-hexane/ethyl acetate=3/)

NMR (300 MHz, CDCl₃): δppm: 0.60(2H,m), 0.76(3H,t,J=7.5 Hz), 1.06(2H,m),1.17-1.35(5H), 1.40(9H,s) 1.56-1.81(5H), 1.92(1H,m), 2.45-2.60(5H),3.29(2H), 4.32(1H,m), 5.46(1H,d,J=7.9 Hz), 7.26-7.40(2H), 7.45-7.59(2H),7.70(1H,d,J=7.9 Hz), 7.84(1H,d,J=7.9 Hz), 8.00(1H,d,J=7.9 Hz)

(b) 23.5 mg of L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine tert-butyl esterwas dissolved in 0.2 ml of dichloromethane, and 0.1 ml of trifluoroacetic acid was added thereto. The mixture was stirred at roomtemperature for four hours. Then, the reaction solution was concentratedunder reduced pressure to obtain 20.7 mg of L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine as colorlesssolid.

Rf: 0.39 (chloroform/methanol/acetic acid=10/0.5/0.1)

(5) (2RS,4S,5S)-5-{L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

20.7 mg of L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine was dissolved in0.5 ml of dry DMF. Then, 17.4 μl of triethylamine, 12.9 μl of DPPA and20 mg of (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide monohydrochloride was added thereto under stirring at -15°C. The mixture was stirred at the same temperature for one hour and thenat 5° C. overnight. The reaction solution was diluted with 20 ml ofethyl acetate, washed with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. Then, thesolvent was distilled off under reduced pressure. The residue waspurified by silica gel column chromatography (chloroform/methanol=50/1)to obtain 16.9 mg of (2RS,4S,5S)-5-{L-N-[(2R orS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucyl}-amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide as colorless solid.

Rf: 0.30, 0.34 (chloroform/methanol=20/1)

Mass spectrum m/z 670(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.80-0.98(18H), 1.14-1.90(22H),2.18(0.5H,m), 2.31(0.5H,m), 2.39-2.64(4H), 2.93-3.42(4H), 3.60(1H,m)3.83(1H,m), 4.31(1H,m), 5.80(0.5H,m), 5.92-6.18(2H), 6.28(0.5H,m),7.22-7.40(2H), 7.45-7.58(2H,m), 7.72(1H,d,J=7.9 Hz), 7.85(1H,d,J=7.9Hz), 7.98(1H,m)

EXAMPLE 13 (2RS,4S,5S)-5-{L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmehtyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

(1) L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine tert-butylester

600 mg ofL-N-[(2RS)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucinetert-butyl ester was dissolved in 10 ml of methanol, and 2.3 ml of ahydrogen peroxide aqueous solution (30%) and 65 mg of sodium tungstatedehydrate were added thereto. The mixture was stirred at roomtemperature for 30 minutes. The reaction solution was diluted with 100ml of ethyl acetate and washed with water and with a saturated sodiumchloride aqueous solution and then dried over anhydrous sodium sulfate.The solvent was distilled off, and the residue was purified by silicagel column chromatography to obtain 315 mg of an isomer having a high Rfvalue of L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine tert-butylester and 318 mg of an isomer having a low Rf value.

Isomer having a high Rf value

Rf: 0.29 (benzene/ethyl acetate=3/1)

NMR (300 MHz, CDCl₃): δppm: 0.87(3H,t,J=7.1 Hz), 1.04-1.45(16H),1.50-2.05(6H), 2.58(1H,m), 2.90(4H,m), 3.20(2H,m), 3.38(2H,m),4.30(1H,m), 5.80(1H,d,J=7.9 Hz), 7.24-7.40(2H), 7.52(2H,m),7.72(1H,d,J=7.9 Hz), 7.85(1H,d,J=7.9 Hz) 8.00(1H,d,J=7.9 Hz)

Isomer having a low Rf value

Rf: 0.27 (benzene/ethyl acetate=3/1)

(2) L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine

25.8 mg of the isomer having a high Rf value of L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine tert-butylester was dissolved in 0.2 ml of dichloromethane. Then, 0.1 ml of TFAwas added thereto, and the mixture was stirred at room temperature for 4hours Then, the reaction solution was concentrated under reducedpressure. The residue thereby obtained was diluted with diethyl etherand concentrated under reduced pressure. This operation was repeated toobtain 22.9 mg of L-N-[(2R or S)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine.

Rf: 0.35 (chloroform/methanol/acetic acid=10/0.5/0.1)

(3) (2RS,4S,5S)-5-{L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

22.9 mg of L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine wasdissolved in 0.2 ml of dry DMF, and 6.23 mg of triethylamine and 16.9 mgof DPPA were added under stirring at -15° C. Then, 26.8 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide monohydrochloride was dissolved in 0.1 ml of dry DMF andneutralized with 8.79 mg of triethylamine. This dry DMF solution wasadded to the previous reaction solution, and the mixture was stirred at-10° C. for one hour and at 5° C. overnight. The reaction solution wasdiluted with 20 ml of ethyl acetate, and the ethyl acetate layer waswashed with water and with a saturated sodium chloride aqueous solutionand dried over anhydrous sodium sulfate. Then, the solvent was distilledoff, and the residue thereby obtained was purified by silica gel columnchromatography (chloroform/methanol=75/1) to obtain 18.2 mg of (2RS,4S,5S)-5-(L-N-[(2R orS)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide as colorless solid.

Rf: 0.27, 0.31 (chloroform/methanol=20/1)

Mass spectrum m/z 702(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.80-1.00(18H), 1.17-1.40(8H),1.40-1.70(7H), 1.70-2.00(6H), 2.20(0.5H,m), 2.30(0.5H,m), 2.62(1H,m),2.78-3.08(4H), 3.18(2H,m) 3.35(2H,m), 3.62(1H,m), 3.82(1H,m),4.26(1H,m), 5.78(0.5H,m), 5.86(0.5H,m), 6.05(2H,m), 7.22-7.42(2H),7.52(2H,m), 7.74(1H,d,J=7.9 Hz), 7.86(1H,d,J=7.9 Hz), 7.96(1H,d,J=7.9Hz)

EXAMPLE 14 (2RS,4S,5S)-5-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide

(a) 53 mg of L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine methyl ester was dissolved in 0.8 ml ofmethanol/water (10/1), and 0.387 ml of a solution of 1N potassiumhydroxide in methanol/water (10/1) was added thereto. The mixture wasstirred at room temperature for 50 minutes. The mixture was neutralizedwith 1N hydrochloric acid under cooling with ice, and 20 ml of ethylacetate was added thereto. The ethyl acetate layer was washed with waterand with a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The solvent was distilled off, and the residuethereby obtained was purified by silica gel column chromatography(chloroform/methanol/acetic acid=15/1/0.15). The fractions containingthe desired product were collected, and the organic layer was washedwith a 4% sodium hydrogencarbonate aqueous solution and with a saturatedsodium chloride aqueous solution and dried over anhydrous sodiumsulfate. Then, the solvent was distilled off to obtain 49 mg ofL-N.sup.α -[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine as colorless solid.

Rf: 0.56, 0.44 (chloroform/methanol/acetic acid=10/1.5/0.1)

(b) 33.5 mg of L-N.sup.α-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine was dissolved in 0.4 ml of dry DMF, and 5.92mg of triethylamine and 16.1 mg of DPPA were added thereto understirring at -15° C. Further, 6.9 mg of triethylamine and a dry DMFsolution (0.4 ml) of 21.1 mg of(2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide monohydrochloride were added thereto, and the mixture wasstirred at the same temperature for two hours and at room temperatureovernight. The reaction solution was diluted with 20 ml of ethylacetate, and the ethyl acetate layer was washed with water and with asaturated sodium chloride aqueous solution and dried over anhydroussodium sulfate. Then, the solvent was distilled off, and the residue waspurified by silica gel column chromatography (chloroform/methanol=40/1)to obtain 37.5 mg of (2RS,4S,5S)-5-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide as colorless solid.

Rf: 0.27 (chloroform/methanol=20/1)

Mass spectrum m/z 940(M⁺ +1)

EXAMPLE 15 (2RS,4S,5S)-5-{L-N.sup.α-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide

28 mg of (2RS,4S,5S)-5-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoic acidisobutylamide obtained in the above step (b) was dissolved in 0.4 ml ofdichloromethane, and 0.1 ml of TFA was added thereto. The mixture wasstirred at room temperature for 3 hours. The solvent was distilled off,and benzene was added to the residue, and the solvent was distilled off.This operation was repeated twice. The residue was dissolved in 15 ml ofethyl acetate, and the ethyl acetate layer was washed with a 4% sodiumhydrogencarbonate aqueous solution with water and with saturated sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Thesolvent was distilled off, the residue was purified by silica gel columnchromatography (chloroform/methanol=20/1) to obtain 6.2 mg of(2RS,4S,5S)-5-{L-N.sup.α-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-2-ethyl-4-hydroxy-7-methyloctanoicacid isobutylamide.

Rf: 0.11 (chloroform/methanol=10/1)

Mass spectrum m/z 698(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.56-1.00(14H), 1.10-1.81(12H), 2.24(0.5H),2.34(0.5H), 2.70-3.28(9H), 3.40-3.88(5H), 4.72(1H,br), 6.44(1H,br),6.56(1H,br), 6.94(1H), 7.22-7.40(2H), 7.40-7.55(3H) 7.72(1H,d,J=7.9 Hz),7.82(1H,m), 8.02(1H,m)

EXAMPLE 16(2RS,3RS,4S)-4-{L-N-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentandiol

(1) L-N-benzyloxycarbonylcyclohexylalanine 3,5-dimethylpyrazolide

(a) 2 g of L-phenylalanine was dissolved in 30 ml of 50% acetic acid,and high pressure hydrogenation was conducted (hydrogen pressure: 50kg/cm², 40°-70° C., two hours) by an addition of 200 mg of platinumoxide. The catalyst was removed by filtration, and the solvent wasdistilled off under reduced pressure to obtain 2.2 g ofL-cyclohexylalanine as colorless needles.

(b) 2.2 g of L-cyclohexylalanine was suspended in 8 ml of water anddissolved by an addition of 2.7 ml of triethylamine. Then, 8 ml of adioxane solution of 4.2 g ofS-(benzyloxycarbonyl)-4,6-dimethyl-2-mercaptopyrimidine was addedthereto, and the mixture was stirred at room temperature for two hours.After an addition of 100 ml of water, the reaction mixture was extractedwith ethyl acetate. Then, the aqueous layer was adjusted to pH2 with 6Nhydrochloric acid at 0° C. The aqueous layer was extracted with ethylacetate, and the ethyl acetate layer was washed with 1N hydrochloricacid and a saturated sodium chloride aqueous solution and then driedover anhydrous magnesium sulfate. The solvent was distilled off underreduced pressure to obtain 4.1 g ofL-N-benzyloxycarbonylcyclohexylalanine as colorless oily substance.

Rf: 0.48 (benzene/methanol/acetic acid=10/1/0.5)

(c) 2 g of L-N-benzyloxycarbonylcyclohexylalanine was dissolved in 20 mlof dichloromethane, and 0.84 g of 3,5-dimethylpyrazole was addedthereto. Further, 1.0 g of DCC was added thereto, and the mixture wasstirred at from 0° to 8° C. overnight. The precipitates were removed byfiltration, and the solvent was distilled off under reduced pressure.The residue was dissolved in ethyl acetate, and the solution was washedwith a 10% citric acid aqueous solution, water, a 4% sodiumhydrogencarbonate aqueous solution, water and a saturated sodiumchloride aqueous solution and dried over anhydrous magnesium sulfate.Then, the solvent was distilled off under reduced pressure, and theresidue was crystallized from diethyl ether/n-hexane to obtain 2.1 g ofL-N-benzyloxycarbonylcyclohexylalanine 3,5-dimethylpyrazolide ascolorless needles.

mp: 93°-94° C.

Rf: 0.45 (n-hexane/ethyl acetate=3/1)

(2) (3RS,4S)-4-(benzyloxycarbonyl)amino-5-cyclohexyl-3-hydroxypentene

(a) 792 mg of lithium aluminum hydride was suspended in 50 ml of dryTHF. Then, 50 ml of a dry THF solution of 4 g ofL-N-benzyloxycarbonylcyclohexylalanine 3,5-dimethylpyrazolide wasdropwise added thereto over a period of about 40 minutes at -40° to -45°C. under argon. The mixture was further stirred at the same temperaturefor 20 minutes, and then 5 ml of 5N hydrochloric acid was added thereto.The insolubles were removed by filtration, and the solvent was distilledoff under reduced pressure. The residue was dissolved in ethyl acetate.The ethyl acetate layer was washed with 1N hydrochloric acid and with asaturated sodium chloride aqueous solution and then dried over anhydrousmagnesium sulfate. Then, the solvent was distilled off under reducedpressure to obtain 3.4 g of L-N-benzyloxycarbonylcyclohexylalaninal ascolorless oily substance.

Rf: 0.30 (n-hexane/ethyl acetate=4/1)

(b) 3.4 g of L-N-benzyloxycarbonylcyclohexyalaninal was dissolved in 25ml of dry THF. Then, 36 ml of a THF solution of 0.88M vinyl magnesiumbromide was dropwise added thereto over a period of 40 minutes at -78°C. under an argon gas atmosphere. After completion of the dropwiseaddition, the reaction mixture was returned to room temperature andstirred at room temperature for 30 minutes. The reaction solution waspoured into 250 ml of a saturated ammonium chloride aqueous solution andextracted with ethyl acetate. The ethyl acetate layer was washed with asaturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. Then, the solvent was distilled off under reducedpressure. The residue was purified by silica gel column chromatography(toluene/ethyl acetate=7/1) to obtain 1.9 g of the above identifiedcompound as colorless oily substance.

Rf: 0.18 (n-hexane/ethyl acetate=4/1)

(3)(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-5-ethenyl-2,2-dimethyloxazolidine

983 mg of (3RS,4S)-4-(benzyloxycarbonyl)amino-5-cyclohexylpentene-3-olwas dissolved in 5 ml of dichloromethane, and 4 ml of2,2-dimethoxypropane and 30 mg of dry p-toluenesulfonic acid were addedthereto. The mixture was stirred at room temperature overnight. Then,100 ml of ethyl acetate was added to the reaction mixture. The mixturewas washed with a saturated sodium hydrogencarbonate aqueous solutionand with a saturated sodium chloride aqueous solution. Then, the organiclayer was dried over anhydrous magnesium sulfate. The solvent wasdistilled off under reduced pressure, and the residue was purifiedby-silica gel column chromatography (n-hexane/ethyl acetate=20/1) toobtain 967 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-5-ethenyl-2,2-dimethyloxazolidineas colorless oily substance.

Rf: 0.74 (n-hexane/ethyl acetate=3/1)

(4)(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-morpholinoethyl]oxazolidine

(a) 440 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-5-ethenyl-2,2-dimethyloxazolidinewas dissolved in 12 ml of dichloromethane, and 850 mg ofm-chloroperbenzoic acid (hereinafter referred to simply as MCPBA) wasadded thereto. The mixture was stirred at room temperature overnight,and then refluxed under heating for three hours. Then, 60 ml of ethylacetate was added to the reaction mixture, and the mixture was washedwith a 10% sodium hydrogensulfite aqueous solution a saturated sodiumhydrogencarbonate aqueous solution and a saturated sodium chlorideaqueous solution. The ethyl acetate layer was dried over anhydrousmagnesium sulfate, and then the solvent was distilled off under reducedpressure. The residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=10/1) to obtain 318 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneas colorless oily substance.

Rf: 0.19 (n-hexane/ethyl acetate=10/1)

(b) 80 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiranewas dissolved in 3.5 ml of methanol, and 22 μl of morpholine was addedthereto. The mixture was refluxed under heating for five hours. Thereaction mixture was subjected to distillation under reduced pressure toremove the solvent. The residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=1/1) to obtain 78 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-morpholinoethyl]oxazolidineas colorless oily substance.

Rf: 0.23, 0.32 (n-hexane/ethyl acetate=1/1)

(5)(2RS,3RS,4S)-4-{L-N-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 61 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS-1-hydroxymorpholinoethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. Then, hydrogenation was conducted at room temperature underatmospheric pressure. The catalyst was removed by filtration, and thesolvent was distilled off under reduced pressure to obtain 38 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol ascolorless oily substance.

Rf: 0.32, 0.42 (chloroform/methanol/aqueous ammonia=10/2/0.2)

(b) 18 mg ofL-N-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.2 ml of dry DMF. Then, 8 μl of triethylamine, 11 μl ofDPPA and a solution of 18.4 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol in 0.4 mlof dry DMF, were added thereto under stirring at -15° C. The mixture wasstirred at room temperature ovenight. Then, 20 ml of ethyl acetate wasadded to the reaction mixture, and the mixture was washed with water anda saturated sodium chloride aqueous solution. The ethyl acetate layerwas dried over anhydrous magnesium sulfate, and then the solvent wasdistilled off under reduced pressure. The residue was purified by silicagel column chromatography (chloroform/methanol=100/1) to obtain 10.9 mgof the above identified compound as colorless powder.

Rf: 0.20 (chloroform/methanol=20/1)

Mass spectrum m/z 688(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.82-0.97(3H,m), 1.20(3H,t,J=7.6 Hz),1.12-1.85(19H,m), 2.42-2.58(2H,m), 2.58-2.91(6H,m),3.03(1H,dd,J=13.7,3.4 Hz), 3.25-3.78(11H,m), 4.19-4.33(2H,m),6.01(1H,d,J=7.9 Hz), 6.09(1H,d,J=6.3 Hz), 7.33-7.69(4H,m),7.82(1H,d,J=7.9 Hz), 7.92(1H,d,J=7.9 Hz), 8.03(1H,d,J=7.9 Hz)

EXAMPLE 17(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-piperidino-2,3-pentanediol

(a) 62 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained in step (4)-(a) of Example 16 was dissolved in 2.6 ml ofmethanol, and 18 μl of piperidine was added thereto. The mixture wasrefluxed under heating for 5 hours. The reaction solution was subjectedto distillation under reduced pressure to remove the solvent. Theresidue was purified by silica gel column chromatography(n-hexane./ethyl acetate=1/1) to obtain 73 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-piperidinoethyl]oxazolidineas colorless oily substance.

Rf: 0.5 (n-hexane/ethyl acetate=1/1)

(b) 71 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-piperidinoethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. Then, hydrogenation was conducted at room temperature underatmospheric pressure. The catalyst was removed by filtration, and thenthe solvent was distilled off under reduced pressure to obtain 41 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-piperidino-2,3-pentanediol ascolorless oily substance.

Rf: 0.41 (chloroform/methanol/aqueous ammonia=10/2/0.2)

(c) 45 mg ofL-N-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.5 ml of dry DMF. Then, 18 μl of triethylamine, 28 μl ofDPPA and 0.5 ml of a dry DMF solution of 41 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-piperidino-2,3,-pentanediol, wereadded thereto under stirring at -15° C. The mixture was stirred at roomtemperature overnight, and then treated in the same manner as in step(5)-(b) of Example 16. The product, was purified by silica gel columnchromatography (chloroform/methanol=20/1) to obtain 30.2 mg of the aboveidentified compound as white powder.

Rf: 0.30 (chloroform/methanol=10/1)

Mass spectrum (FAB) m/z 686(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.80-0.92(3H,m), 1.20(3H,t,J=7.6 Hz)0.92-1.84(25H,m), 2.25-2.50(2H,m) 2.50-2.90(6H,m), 3.02(1H,dd,J=13.7,3.4Hz), 3.25-3.52(5H,m), 3.56-3.69(1H,m), 4.18-4.30(2H,m), 5.89-6.18(2H,m),7.35-7.49(2H,m), 7.49-7.65(2H,m), 7.79(1H,d,J=7.9 Hz), 7.90(1H,d,J=7.9Hz), 8.03(1H,d,J=7.9 Hz)

EXAMPLE 18(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-(4-methylpiperidino)-2,3-pentanediol

(a) 62 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained in Example 16 (4)-(a) was dissolved in 2.6 ml of methanol, and21 μl of 4-methylpiperidine was added thereto. The mixture was treatedin the same manner as in Example 17. The product was purified by silicagel column chromatography (n-hexane/ethyl acetate=1/2) to obtain 72 mgof(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(4-methylpiperidino)ethyl]oxazolidineas colorless oily substance.

Rf: 0.13-0.41 (n-hexane/ethyl acetate=1/2)

(b) 70 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(4-methylpiperidino)ethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. The mixture was treated in the same manner as in Example 17 toobtain 45 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(4-methylpiperidino)-2,3-pentanediolas colorless oily substance.

Rf: 0.47 (chloroform/methanol/aqueous ammonia=10/2/0.2)

(c) 43 mg ofL-N-[2(S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.4 ml of dry DMF. Then, 17 μl of triethylamine, 27 μl ofDPPA and 0.6 ml of a dry DMF solution of 45 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(4-methylpiperidino)-2,3-pentanediol,were added thereto under stirring at -15° C. The mixture was treated inthe same manner as in Example 16 (5)-(b). The product was purified bysilica gel column chromatography (chloroform/methanol=20/1) to obtain36.5 mg of the above identified compound as white powder.

Rf: 0.29 (chloroform/methanol=10/1)

Mass spectrum (FAB) m/z 700(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.78-0.92(6H,m), 0.92-1.82(27H,m),1.90-2.04(1H,m), 2.17-2.31(1H,m), 2.51-2.91(5H,m), 3.00(1H,dd,J=13.7,3.4Hz), 3.05-3.18(1H,m), 3.24-3.49(5H,m), 3.61(1H,dd,J=15.0,7.9 Hz),4.15-4.29(2H,m), 5.88-6.01(1H,6s), 6.01-6.18(1H,6s), 7.32-7.46(2H,m),7.46-7.63(2H,m), 7.78(1H,d,J=7.9 Hz) 7.38(1H,d,J=7.9 Hz),8.01(1H,d,J=7.9 Hz)

EXAMPLE 19(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-6-methyl-1-morpholino-2,3-heptanediol

(1) (3RS,4S)-4-(benzyloxycarbonyl)amino-6-methylhepten-3-ol

(a) 120 mg of lithium aluminum hydride was suspended in 3 ml of dry THF,and 12 ml of a dry THF solution of 1 g of L-N-benzyloxycarbonylleucinepirazolide was dropwise added over a period of 35 minutes at -35° to-40° C. under an argon gas atmosphere. The mixture was left at the sametemperature for one hour, and then 0.64 ml of 5N hydrochloric acid wasadded thereto. The insolubles were removed by filtration, and thesolvent was distilled off under reduced pressure from the filtrate. Theresidue was dissolved in ethyl acetate. The ethyl acetate layer waswashed with 1N hydrochloric acid and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. The solventwas distilled off under reduced pressure to obtain 634 mg ofL-N-benzyloxycarbonylleucinal as colorless oily substance.

Rf: 0.34 (n-hexane/ethyl acetate=3/1)

(b) 634 mg of L-N-benzyloxycarbonylleucinal was dissolved in 7 ml of dryTHF, and 10 ml of a THF solution of 0.87M vinyl magnesium bromide wasdropwise added over a period of 25 minutes at -78° C. under an argon gasatmosphere. After completion of the dropwise addition, the reactionmixture was returned to room temperature and further stirred for 15hours. The reaction solution was poured into 20 ml of a saturatedammonium chloride aqueous solution and extracted with diethyl ether. Theether layer was washed with a saturated sodium chloride aqueous solutionand dried over anhydrous magnesium sulfate. The solvent was distilledoff under reduced pressure. The residue was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=5/1) to obtain 384 mg of(3RS,4S)-4-(benzyloxycarbonyl)amino-6-methylhepten-3-ol as colorlessoily substance.

Rf: 0.29 (n-hexane/ethyl acetate=3/1)

(2)(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-ethenyl-4-isobutyloxazolidine

124 mg of (3RS,4S)-4-(benzyloxycarbonyl)amino-6-methylhepten-3-ol wasdissolved in 0.33 ml of 2,2-dimethoxypropane, and 4 mg of dryp-toluenesulfonic acid was added thereto. The mixture was stirred atroom temperature overnight. Then, 20 ml of ethyl acetate was added tothe reaction solution, and the mixture was washed with a saturatedsodium hydrogencarbonate aqueous solution and a saturated sodiumchloride aqueous solution. The organic layer was dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel columnchromatography-(n-hexane/ethyl acetate=10/1) to obtain 101 mg of(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-ethenyl-4-isobutyloxazolidineas colorless oily substance.

Rf: 0.73 (n-hexane/ethyl acetate=3/1)

(3)(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-morpholinoethyl]-4-isobutyloxazolidine

(a) 98.4 mg of(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-ethenyl-4-isobutyloxazolidinewas dissolved in 6 ml of dichloromethane, and 212 mg of MCPBA was addedthereto. The mixture was stirred at room temeprature for one hour andfuther refluxed for 4.5 hours. Then, 20 ml of ethyl acetate was added tothe reaction solution, and the mixture was washed with a cold 5% sodiumhydrogensulfite aqueous solution, with a saturated sodiumhydrogencarbonate aqueous solution and with a saturated sodium chlorideaqueous solution. The ethyl acetate layer was dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=10/1) to obtain 50 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]oxiraneas colorless oily substance.

Rf: 0.25 (n-hexane/ethyl acetate=5/1)

(b) 48 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]oxiranewas dissolved in 2 ml of methanol, and 14 μl of morpholine was addedthereto. The mixture was refluxed overnight. The reaction solution wassubjected to distillation under reduced pressure for the removal of thesolvent, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=1/1) to obtain 55 mg of(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-morpholinoethyl]-4-isobutyloxazolidineas colorless oily substance.

Rf: 0.32 (n-hexane/ethyl acetate=1/1)

(4)(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-6-methyl-1-morpholino-2,3-heptanediol

(a) 53.7 mg of(4S,5RS)-3-benzyloxycarbonyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-morpholinoethyl]-4-isobutyloxazolidinewas dissolved in 0.8 ml of ethanol, and palladium black was addedthereto. Then, hydrogenation was conducted at room temperature atatmospheric pressure. The catalyst was removed by filtration, and thesolvent was distilled off to obtain 23 mg of(2RS,3RS,4S)-4-amino-6-methyl-1-morpholino-2,3-heptanediol as colorlessoily substance.

Rf: 0.32, 0.43 (chloroform/methanol/aqueous ammonia=10/1/0.2)

(b) 38.8 mg ofL-N-(3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.3 ml of dry DMF. Then, 16 μl of triethylamine, 22 μl ofDPPA and 0.6 ml of a dry DMF solution of 23 mg of(2RS,3RS,4S)-4-amino-6-methyl-1-morpholino-2,3-heptanediol, were addedthereto under stirring at -15° C. The mixture was stirred at roomtemperature overnight. Then, 20 ml of ethyl acetate was added to thereaction mixture, and the mixture was washed with a 10% citric acidsolution, with a 4% sodium hydrogencarbonate aqueous solution and with asaturated sodium chloride aqueous solution. The ethyl acetate layer wasdried over anhydrous magnesium sulfate, and the solvent was distilledoff under reduced pressure. The residue was purified by silica gelcolumn chromatography (chloroform/methanol=50/1) to obtain 19.6 mg ofthe above identified compound as colorless powder.

Rf: 0.23 (chloroform/methanol=30/1)

Mass spectrum m/z 648(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.84(3H,t,J=7.5 Hz), 0.92(3H,d,J=7.5 Hz),0.97(3H,d,J=7.5 Hz), 1.20(3H,t,J=7.5 Hz), 1.20-1.35(4H,m),1.34-1.47(1H,m), 1.47-1.85(5H,m), 2.41-2.55(2H,m), 2.55-2.86(6H,m),3.01(1H,dd,J=2.4,14.4 Hz), 3.22-3.74(10H,m), 4.16-4.26(2H,m),4.58(1H,s), 5.96(1H,d,J=9.4 Hz), 6.08(1H,d,J=7.1 Hz), 7.20-7.62(4H,m),7.78(1H,d,J=7.9 Hz), 7.88(1H,d,J=7.9 Hz), 7.98(1H,d,J=7.9 Hz)

EXAMPLE 20(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-(2-methoxyethylamino)-2,3-pentanediol

(a) 64 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained in Example 16(4)-(a) was dissolved in 2.6 ml of methanol, and16 μl of 2-methoxyethylamine was added thereto. The mixture was treatedin the same manner as in Example 17. The product was purified by silicagel column chromatography (chloroform/methanol=10/1) to obtain 44 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(2-methoxyethylamino)ethyl]oxazolidineas colorless oily substance.

Rf: 0.35 (chlorofrom/methanol=10/1)

(b) 44 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(2-methoxyethylamino)ethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. The mixture was treated in the same manner as in Example 17 toobtain 27 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(2-methoxyethylamino)-2,3-pentanediolas colorless oily substance.

Rf: 0.17, 0.29 (chloroform/methanol/ammonia=10/2/0.2)

(c) 29 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.4 ml of dry DMF. Then, 11.4 μl of triethylamine, 18 μl ofDPPA and 0.6 ml of a dry DMF solution of 27 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(2-methoxyethylamino)-2,3-pentanediol,were added thereto under stirring at -15° C. The mixture was treated inthe same manner as in Example 16 (5)-(b). The product was purified bysilica gel column chromatography (chloroform/methanol=20/1) to obtain12.8 mg of the above identified compound as white powder.

Rf: 0.21 (chloroform/methanol=10/1)

Mass spectrum m/z 677(M⁺ +1)

NMR (300 MHz,CDCl₃): δppm: 0.87(3H,t,J=7.1 Hz), 1.16(3H,t,J=7.9 Hz),0.92-1.86(19H,m), 2.20-2.97(6H,m), 3.02(1H,dd,J=13.7,3.4 Hz),3.18(1H,dd,J=12.0,4.7 Hz), 3.24-3.61(6H,m), 3,47(3H,t,J=7.1 Hz),3.70(1H,dd,J=14.2,7.9 Hz), 4.14-4.26(2H,m), 6.40(1H,bs), 6.57(1H,bs),7.34-7.48(2H,m), 7.48-7.64(2H,m), 7.79(1H,d,J=7.9 Hz), 7.88(1H,d,J=7.9Hz), 8.03(1H,d,J=7.9 Hz)

EXAMPLE 21 (2RS,3R orS,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-methylthio-2,3-pentanediol

(1) L-N-tert-butoxycarbonylcyclohexylalanine 3,5-dimethylpyrazole

(a) 1.0 g of L-cyclohexylalanine obtained in the process of Example 16(1)-(a) was suspended in 5 ml of water, and 1.2 ml of triethylamine wasadded thereto. 5 ml of a dioxane solution of 1.7 g ofS-(tert-butoxycarbonyl)-4,6-dimethyl-2-mercaptopyrimidine was addedthereto, and the mixture was stirred at room temperature for 18 hours.Then, 50 ml of water was added to the reaction mixture, and the mixturewas extracted with ethyl acetate. The aqueous layer was adjusted pH4with 5N hydrochloric acid under cooling with ice and extracted withethyl acetate. The ethyl acetate layer was washed with 1N hydrochloricacid and with a saturated sodium chloride aqueous solution and driedover anhydrous magnesium sulfate. The solvent was distilled off underreduced pressure to obtain 1.1 g ofL-N-tert-butoxycarbonylcyclohexylalanine as slightly yellow oilysubstance.

Rf: 0.35 (chloroform/methanol/acetic acid=20/1/0.5)

(b) 1.4 g of L-N-tert-butoxycarbonylcyclohexylalanine was dissolved in20 ml of dichloromethane, and 0.54 g of 3,5-dimethylpyrazole was addedthereto. Further, 1.15 g of DCC was added under cooling with ice, andthe mixture was stirred at room temperature overnight. The precipitateswere removed by filtration, and the solvent was distilled off underreduced pressure. The residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=5/1) to obtain 1.75 g ofL-N-tert-butoxycarbonylcyclohexylalanine 3,5-dimethylpyrazolide ascolorless oily substance.

Rf: 0.70 (n-hexane/ethyl acetate=3/1)

(2) (3RS,4S)-4-(tert-butoxycarbonyl)amino-5-cyclohexylpenten-3-ol

(a) 192 mg of lithium aluminum hydride was suspended in 5 ml of dry THF.Then, 20 ml of a dry THF solution of 1.58 g ofL-N-tert-butoxycarbonylcyclohexylalanine 3,5-dimethylpyrazolide wasdropwise added over a period of about 40 minutes at about -40° C. underan argon gas atmosphere. Then, the mixture was left at the sametemperature for one hour and 20 minutes, and then 1 ml of 5Nhydrochloric acid was added thereto. The insolubles were removed byfiltration, and the solvent was distilled off under reduced pressure.The residue was dissolved in ethyl acetate. The ethyl acetate layer waswashed with 1N hydrochloric acid and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. The solventwas distilled off under reduced pressure to obtain 0.91 g ofL-N-tert-butoxycarbonyl cyclohexylalaninal as colorless oily substance.

Rf: 0.58 (n-hexane/ethyl acetate=3/1)

(b) 0.91 g of L-N-tert-butoxycarbonyl cyclohexylalaninal was dissolvedin 12 ml of dry THF, and 16 ml of a THF solution of 0.87M vinylmagnesium bromide was dropwise added over a period of 45 minutes at -78°C. under an argon gas atmosphere. After completion of the dropwiseaddition, the reaction mixture was returned to room temperature andfurther stirred overnight. The reaction solution was poured into 30 mlof a saturated ammonium chloride aqueous solution and extracted withethyl acetate. The ethyl acetate layer was washed with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. Then, the solvent was distilled off under reduced pressure. Theresidue was purified by silica gel column chromatography (n-hexane/ethylacetate=5/1) to obtain 0.3 g of the above identified compound ascolorless oily substance.

Rf: 0.41 (n-hexane/ethyl acetate=3/1)

(3)(4S,5RS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-ethenyloxazolidine

293 mg of (3RS,4S)-4-(tert-butoxycarbonyl)amino-5-cyclohexyl penten-3-olwas dissolved in 0.78 ml of 2,2-dimethoxypropane, and 9 mg of dryp-toluenesulfonic acid was added thereto. The mixture was stirred atroom temperature overnight. Then, 20 ml of ethyl acetate was added tothe reaction mixture, and the mixture was washed with a saturated sodiumhydrogencarbonate aqueous solution and with a saturated sodium chlorideaqueous solution. Then, the organic layer was dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=10/1) to obtain 259 mg of the above identifiedcompound as colorless oily substance.

Rf: 0.80 (n-hexane/ethyl acetate=3/1)

(4) (4S,5R orS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-methylthioethyl]oxazolidine

(a) 145 mg of(4S,5RS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-ethenyloxazolidinewas dissolved in 4.5 ml of dichloromethane, and 309 mg of MCPBA wasadded thereto. The mixture was refluxed under heating for 5 hours. Then,50 ml of ethyl acetate was added to the reaction mixture, and themixture was washed with a 1N sodium hydroxide aqueous solution and witha saturated sodium chloride aqueous solution. The organic layer wasdried over anhydrous magnesium sulfate. Then, the solvent was distilledoff under reduced pressure, and the residue was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=10/1) to obtain 75.1 mg of(1RS)-1-[(4S,5RS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneas colorless oily substance.

Rf: 0.69 (n-hexane/ethyl acetate=3/1)

(b) 70 mg of-(1RS)-1-[(4S,5RS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiranewas dissolved in 3 ml of methanol, and 106 μl of sodium methylmercaptanaqueous solution (15%) was added thereto. The mixture was refluxed underheating for five hours. Then, ethyl acetate was added to the reactionsolution, and the mixture was washed with water and with a saturatedsodium chloride aqueous solution. The organic layer was dried overanhydrous magnesium sulfate. Then, the solvent was distilled off underreduced pressure, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=10/1) to obtain 29.8 mg of (4S,5RorS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-methylthioethyl]oxazolidineas white solid.

Rf: 0.68 (n-hexane/ethyl acetate=3/1)

(5) (2RS,3R orS,4S)-4-{L-N-[3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-methylthio-2,3-pentanediol

(a) 29.4 mg of (4S,5R orS)-3-tert-butoxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-methylthioethyl]oxazolidinewas dissolved in 0.3 ml of dioxane, and 0.42 ml of a dioxane solution of3.6M hydrogen chloride was added thereto. From the reaction solution,the solvent was distilled off under reduced pressure to obtain 22.5 mgof (2RS,3R or S,4S)-4-amino-5-cyclohexyl-1-methylthio-2,3-pentanediolhydrochloride as colorless oily substance.

Rf: 0.66 (chloroform/methanol/aqueous ammonia=10/1/0.5)

(b) 18 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.1 ml of dry DMF. Then, 20 μl of triethylamine, 14 μl ofDPPA and 0.5 ml of a dry DMF solution of 22.5 mg of (2RS,3R orS,4S)-4-amino-5-cyclohexyl-1-methylthio-2,3-pentanediol hydrochloride,were added under stirring at -15° C. The mixture was stirred at roomtemperature overnight. Then, 20 ml of ethyl acetate was added to thereaction solution, and the mixture was washed with water and with asaturated sodium chloride aqueous solution. The ethyl acetate layer wasdried over anhydrous magnesium sulfate. Then, the solvent was distilledoff under reduced pressure. The residue was purified by silica gelcolumn chromatography (chloroform/methanol=100/1) to obtain 18.5 mg ofthe above identified compound as colorless solid.

Rf: 0.27 (chloroform/methanol=30/1)

Mass spectrum m/z 649(M⁺ +1)

NMR (300 MHz, CDCl₃) δppm: 0.85(3H,t,J=7.6 Hz), 0.80-1.10(2H,m),1.10-1.50(9H,m),1.25(3H,t,J=7.6 Hz), 1.50-1.92(6H,m), 2.18(3H,s),2.64-2.98(5H,m), 3.08(1H,dd,J=2,14 Hz), 3.28-3.66(7H,m), 4.03(1H,m),4.24(1H,m), 4.45(1H,d,J=3 Hz), 6.08(1H,d,J=6 Hz), 6.46(1H,d,J=9 Hz),7.20-7.63(4H,m), 7.80(1H,d,J=8 Hz), 7.90(1H,d,J=8 Hz) 8.00(1H,d,J=8 Hz)

EXAMPLE 22(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-(2-hyydroxyethylamino)-2,3-pentanediol

(a) 67 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained in Example 16 (4)-(a) was dissolved in 2.6 ml of methanol.Then, 12 μl of 2-ethanolamine was added thereto. The mixture was treatedin the same manner as in Example 17. The product was purified by silicagel column chromatography (chloroform/methanol=10/1, 5/1) to obtain 39.7mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(2-hydroxyethylamino)ethyl]oxazolidineas colorless oily substance.

Rf: 0.15-0.35 (chloroform/methanol=5/1)

(b) 38.5 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(2-hydroxyethylamino)ethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. The mixture was treated in the same manner as in Example 17 toobtain 25.8 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(2-hydroxyethylamino)-2,3-pentanediolas colorless oily substance.

Rf: 0.05, 0.08 (chloroform/methanol/aqueous ammonia=10/2/0.2)

(c) 23 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.3 ml of dry DMF. Then, 10.4 μl of triethylamine, 16 μl ofDPPA and 0.6 ml of a dry DMF solution of 25.8 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-(2-hydroxyethylamino)-2,3-pentanediolwere added thereto under stirring at -15° C. The mixture was treated inthe same manner as in Example 16 (5)-(b), and the product was purifiedby silica gel column chromatography (chloroform/methanol=5/1) to obtain13.1 mg of the above identified compound as white powder.

Rf: 0.30-0.41 (chloroform/methanol=5/1)

Mass spectrum (FAB) m/z 662(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.70-2.20(25H,m), 2.61-2.99(7H,m)3.08-3.92(11H,m), 3.99-4.19(2H,m) 6.90-7.01(2H,m), 7.28-7.41(2H,m),7.41-7.59(2H,m), 7.75(1H,d,J=7.9 Hz), 7.85(1H,d,J=7.9 Hz),8.08(1H,d,J=7.9 Hz)

EXAMPLE 23(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-diethylamino-2,3-pentanediol

(a) 62 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained in Example 16 (4)-(a) was dissolved in 2.6 ml of methanol, and19 μl of diethylamine was added thereto. The mixture was treated in thesame manner as in Example 17. The product was purified by silica gelcolumn chromatography (chloroform/methanol=10/1) to obtain 45.5 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(diethylamino)ethyl]oxazolidineas colorless oily substance.

Rf: 0.38 (chloroform/methanol=10.1)

(b) 44 mg of(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-[(1RS)-1-hydroxy-2-(diethylamino)ethyl]oxazolidinewas dissolved in 1.5 ml of ethanol, and palladium black was addedthereto. The mixture was treated in the same manner as in Example 17 toobtain 29.5 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-diethylamino-2,3-pentanediol ascolorless oily substance.

Rf: 0.31, 0.41 (chloroform/methanol/aqueous ammonia=10/2/0.2)

(c) 28 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.3 ml of dry DMF, and 12 μl of triethylamine, 18 μl ofDPPA and 0.6 ml of a dry DMF solution of 29.5 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-diethylamino-2,3-pentanediol wereadded thereto under stirring at -15° C. The mixture was treated in thesame manner as in Example 16 (5)-(b). The product was purified by silicagel column chromatography (chloroform/methanol=20/1) to obtain 12.9 mgof the above identified compound as white powder.

Rf: 0.22 (chloroform/methanol=10/1)

Mass spectrum (FAB) m/z 674(M⁺ +1).

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7.1 Hz), 1.20(3H,t,J=7.9 Hz),0.92-1.93(25H,m), 2.37-2.91(8H,m), 3.01(1H,dd,J=13.7,3.4 Hz),3.21-3.53(5H,m), 3.53-3.72(1H,m), 4.15-4.31(2H,m), 5.90-6.39(2H,m),7.31-7.48(2H,m), 7.48-7.66(2H,m), 7.79(1H,d,J=7.9 Hz), 7.89(1H,d,J=7.9Hz), 8.02(1H,d,J=7.9 Hz)

EXAMPLE 24(2RS,3RS,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-[ethyl(2-hydroxyethyl)amino]-2,3-pentanediol

(1)(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyl-5-{(1RS)-2-(ethyl(2-hydroxyethyl)amino]-1-hydroxyethyl}oxazolidine

71 mg of(1RS)-1-[(4S,5RS)-3-benzyloxycarbonyl-4-cyclohexylmethyl-2,2-dimethyloxazolidin-5-yl]oxiraneobtained by the process of Example 16 (4)-(a) was dissolved in 2 ml ofmethanol, and 30 μl of 2-ethylaminoethanol was added thereto. Themixture was refluxed under heating for 7 hours. The solvent wasdistilled off under reduced pressure from the reaction solution. Theresidue was purified by silica gel column chromatography(chloroform/methanol=30/1) to obtain 84 mg of the above identifiedcompound as colorless oily substance.

Rf: 0.48 (chloroform/methanol=10/1)

(2)(2RS,3RS,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-[ethyl(2-hydroxyethyl)amino]-2,3-pentanediol

(a) 83 mg of the compound obtained in step (1) was dissolved in 0.8 mlof ethanol, and palladium black was added thereto. The hydrogenation wasconducted at room temperature under atmospheric pressure. The catalystwas removed by filtration, and the solvent was distilled off underreduced pressure to obtain 49 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-[ethyl(2-hydroxyethyl)amino]-2,3-pentanediolas colorless oily substance.

(b) 52 mg ofL-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}norleucine wasdissolved in 0.3 ml of dry DMF. Then, 21 μl of triethylamine and 32 μlof DPPA were sequentially added thereto at -15° C., and then 0.5 ml of adry DMF solution of 49 mg of(2RS,3RS,4S)-4-amino-5-cyclohexyl-1-[ethyl(2-hydroxyethyl)amino]-2,3-pentanediolwas added thereto. The mixture was stirred at room temperatureovernight, and the reaction solution was diluted by an addition of 20 mlof ethyl acetate. The organic layer was washed with a 10% citric acidaqueous solution, with a 4% sodium hydrogencarbonate aqueous solutionand with a saturated sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure, and the residue was purified by silica gel columnchromatography (chloroform/methanol=10/1) to obtain 17.6 mg of the aboveidentified compound as colorless crystals.

Rf: 0.38 (chloroform/methanol=10/1)

Mass spectrum m/z 690(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.82(3H,t,J=7.6 Hz), 0.80-1.33(22H,m),2.46-2.95(8H,m), 3.12(1H,dd,J=3,14 Hz), 3.28-3.72(8H,m),4.08-4.15(2H,m), 6.00-6.32(2H,m), 7.35-7.60(4H,m), 7.70-7.80(1H,m),7.88(1H,d,J=8 Hz), 7.99(1H,d,J=8 Hz)

EXAMPLE 25(2RS,3RS,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-1-isopropylthio-6-methyl-2,3-heptanediol

(1) (3RS,4S)-4-(tert-butoxycarbonyl)amino-6-methylhepten-3-ol

(a) 5 g of L-N-tert-butoxycarbonylleucine monohydrate was dissolved in50 ml of dichloromethane, and 2.1 g of 3,5-dimethylpyrazole was addedthereto. Further, 4.6 g of DCC was added thereto under cooling with ice,and the mixture was stirred at 0° C. for two hours and at roomtemperature overnight. The precipitates were removed by filtration, andthe solvent was distilled off under reduced pressure. The residue wasrecrystallized from methanol/water and washed with water to obtain 6.2 gof L-N-tert-butoxycarbonylleucine 3,5-dimethylpyrazolide as colorlesscrystals.

Rf: 0.59 (n-hexane/ethyl acetate=3/)

(b) 847 mg of lithium aluminum hydride was suspended in 18 ml of dryTHF, and 72 ml of a dry THF solution of 6.2 g ofL-N-tert-butoxycarbonylleucine 3,5-dimethylpyrazolide was dropwise addedover a period of 30 minutes at -30° C. under an argon gas atmosphere.Further, the mixture was left at the same temperature for one hour, andthen 4.5 ml of 5N hydrochloric acid was added. The insolubles wereremoved by filtration, the solvent was distilled off under reducedpressure. The residue was dissolved in diethyl ether. The organic layerwas washed with 1N hydrochloric acid and with a saturated sodiumchloride aqueous solution and dried over anhydrous magnesium sulfate.The solvent was distilled off under reduced pressure to obtain 3.2 g ofL-N-tert-butoxycarbonylleucinal as slightly yellow oily substance.

Rf: 0.51 (n-hexane/ethyl acetate=3/1)

(c) 3.2 g of L-N-tert-butoxycarbonylleucinal was dissolved in 30 ml ofdry THF, and 50 ml of a THF solution of 0.98M vinyl magnesium bromidewas dropwise added thereto over a period of 30 minutes at -78° C. underan argon gas atmosphere. The reaction solution was returned to roomtemperature and further stirred overnight. The reaction solution waspoured into 20 ml of a saturated ammonium chloride aqueous solution andextracted with diethyl ether. The ether layer was washed with asaturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure.The residue was purified by silica gel column chromatography(n-hexane,/ethyl acetate=5/1) to obtain 1.1 g of(3RS,4S)-4-(tert-butoxycarbonyl)amino-6-methylhepten-3-ol as colorlessoily substance.

Rf: 0.40 (n-hexane/ethyl acetate=3/1)

(2)(1RS)-1-[(1R,2S)-2-(tert-butoxycarbonyl)amino-1-hydroxy-4-methylheptyl]oxirane

(a) 1 g of (3RS,4S)-4-(tert-butoxycarbonyl)amino-6-methylhepten-3-ol wasdissolved in 2 ml of dry DMF, and 743 mg oftert-butyldimethylchlorosilane and 700 mg of imidazole were addedthereto. The mixture was stirred at room temperature overnight. Then,160 ml of ethyl acetate was added to the reaction solution. The mixturewas washed with cooled 1N hydrochloric acid, with a saturated sodiumhydrogencarbonate aqueous solution and a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. The solventwas distilled off under reduced pressure. The residue was purified bysilica gel column chromatography (n-hexane,/ethyl acetate=30/1) toobtain 1.21 g of(3RS,4S)-4-(tert-butoxycarbonyl)amino-3-(tert-butyldimethylsilyl)oxy-6-methylhepteneas colorless oily substance.

Rf: 0.49 (n-hexane/ethyl acetate=20/1)

(b) 1.2 g of(3RS,4S)-4-(tert-butoxycarbonyl)amino-3-(tert-butyldimethylsilyl)oxy-6-methylheptenewas dissolved in 30 ml of dichloromethane, and 2.2 g of MCPBA wasgradually added thereto at 0° C. The temperature was returned to roomtemperature, and the mixture was stirred for 14 hours and then refluxedunder heating for further 4 hours.

To the reaction solution, 210 ml of ethyl acetate was added, mixture waswashed with a cooled 10% sodium sulfite aqueous solution, with asaturated sodium hydrogencarbonate aqueous solution and with a saturatedsodium chloride aqueous solution. The ethy acetate layer was dried overanhydrous magnesium sulfate, and the solvent was distilled off underreduced pressure. The residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=10/1) to obtain 943 mg of(1RS)-1-[(1RS,2S)-2-(tert-butoxycarbonyl)amino-1-(tert-butyldimethylsilyl)oxy-4-methylpentyl]oxiraneas colorless oily substance.

Rf: 0.29 (n-hexane/ethyl acetate=10/1)

(c) 873 mg of(1RS)-1-[(1RS,2S)-2-(tert-butoxycarbonyl)amino-1-(tert-butyldimethylsilyl)oxy-4-methylpentyl]oxiranewas dissolved in 4.5 ml of a THF solution of 1M tetrabutylammoniumfluoride, and the solution was stirred at 0° C. for 30 minutes and atroom temperature for 5.5 hours. To the reaction solution, 100 ml ofethyl acetate was added, and the mixture was washed with water and witha saturated sodium chloride aqueous solution. The organic layer wasdried over anhydrous magnesium sulfate, and then the solvent wasdistilled off under reduced pressure. The residue was purified by silicagel column chormatography (n-hexane/ethyl acetate=5/1) to obtain 520 mgof(1RS)-1-[(1RS,2S)-2-(tert-butoxycarbonyl)amino-1-hydroxy-4-methylpentyl]oxiraneas colorless oily substance.

Rf: 0.13 (n-hexane/ethyl acetate=3/1)

(3)(2RS,3RS,4S)-4-(tert-butoxycarbonyl)amino-1-isopropylthio-6-methyl-2,3-heptanediol

46.7 mg of(1RS)-1-[(1RS,2S)-2-(tert-butoxycarbonyl)amino-1-hydroxy-4-methylpentyl]oxiranewas dissolved in 1.8 ml of methanol, and 50 μl of triethylamine and 33μl of isopropylmercaptan were added thereto. The mixture was refluxedunder heating for 6 hours. The solvent was distilled off under reducedpressure from the reaction solution. The residue was purified by silicagel column chromatography (n-hexane/ethyl acetate=5/1) to obtain 23.7 mgof(2RS,3RS,4S)-4-(tert-butoxycarbonyl)amino-1-isopropylthio-6-methyl-2,3-heptanediolas colorless powder.

Rf: 0.42, 0.49 (n-hexane/ethyl acetate=3/1)

(4)(2RS,3RS,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-1-isopropylthio-6-methyl-2,3-heptanediol

(a) 21 mg of(2RS,3RS,4S)-4-(tert-butoxycarbonyl)amino-1-isopropylthio-6-methyl-2,3-heptanediolwas dissolved in 0.3 ml of dioxane, and 0.32 ml of a 3.6M hydrogenchloride/dioxane solution was added thereto. The mixture was stirred atroom temperature for 4 hours. The solvent was distilled off underreduced pressure from the reaction solution to obtain 16.9 mg of(2RS,3RS,4S)-4-amino-1-isopropylthio-6-methyl-2,3-heptanediolhydrochloride as colorless oily substance.

Rf: 0.22 (chloroform/methanol/aqueous ammonia=10/1/0.2)

(b) 17.3 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine in0.2 ml of dry DMF. Then, 15 μl of triethylamine, 11 μl of DPPA and 0.5ml of a dry DMF solution of 16.9 mg of(2RS,3RS,4S)-4-amino-1-isopropylthio-6-methyl-2,3-heptanediolhydrochloride, were added thereto under stirring at -15° C. The mixturewas stirred at room temperature overnight. Then, 15 ml of ethyl acetatewas added to the reaction solution, and the mixture was washed withwater and with a saturated sodium chloride aqueous solution. The organiclayer was dried over anhydrous magnesium sulfate. The solvent wasdistilled off under reduced pressure. The residue was purified by silicagel column chromatography (chloroform/methanol=100/1) to obtain 19.0 mgof the above identified compound as colorless powder.

Rf: 0.22 (chloroform/methanol=50/1)

Mass spectrum m/z 637(M⁺ +1)

NMR (300 MHz, CDCl₃) δppm: 0.85(3H,t,J=7.8 Hz), 0.90(3H,d,J=7.5 Hz),0.96(3H,d,J=7.5 Hz), 1.13-1.40(12H,m), 1.53-1.90(6H,m), 2.22-3.11(6H,m),4.09(1H,dd,J=5,14 Hz), 4.14-4.25(1H,m), 4.40(1H,br s), 6.16(1H,d,J=7Hz), 6.44(1H,d,J=9 Hz), 7.31-7.46(2H,m), 7.49-7.53(2H,m), 7.79(1H,d,J=8Hz), 7.89(1H,d,J=8 Hz), 7.99(1H,d,J=8 Hz)

EXAMPLE 26(2RS,3RS,4S)-4-[L-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}norleucyl]amino-6-methyl-1-thiomorpholino-2,3-heptanediol

(a) 58.4 mg of(1RS)-1-[(1RS,2S)-2-(tert-butoxycarbonyl)amino-1-hydroxy-4-methylpentyl]oxiraneobtained in step (2) was dissolved in 2.2 ml of methanol, and 24 μl ofthiomorpholine was added thereto. The mixture was refluxed under heatingfor 3 hours. The solvent was distilled off under reduced pressure fromthe reaction solution, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=1/1) to obtain 72.7 mg of(2RS,3RS,4S)-4-(tert-butoxycarboryl)amino-6-methyl-1-thiomorpholino-2,3-heptanediolas colorless powder.

Rf: 0.15, 0.33 (n-hexane/ethyl acetate=1/1)

(b) 68 mg of(2RS,3RS,4S)-4-(tert-butoxycarbonyl)amino-6-methyl-1-thiomorpholino-2,3-heptanediolwas dissolved in 0.5 ml of dioxane, and 1 ml of a 3.6M hydrogenchloride/dioxane solution was added thereto. The mixture was stirred atroom temperature for two hours. The solvent was distilled off underreduced pressure from the reaction solution to obtain 63 mg of(2RS,3RS,4S)-4-amino-6-methyl-1-thiomorpholino-2,3-heptanedioldihydrochloride as colorless oily substance.

Rf: 0.38, 0.43 (chloroform/methanol/aqueous ammonia=10/1/0.2)

(c) 51.2 mg ofL-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}norleucine wasdissolved in 0.3 ml of dry DMF. Then, 69 μl of triethylamine, 32 μl ofDPPA and a dry DMF solution of 63 mg of(2RS,3RS,4S)-4-amino-6-methyl-1-thiomorpholino-2,3-heptanedioldihydrochloride, were added thereto under stirring at -15° C. Themixture was stirred at room temperature overnight. Then, 30 ml of ethylacetate was added to the reaction solution, and the mixture was washedwith water and with a saturated soidum chloride aqueous solution. Theethyl acetate layer was dried over anhydrous magnesium sulfate. Then,the solvent was distilled off, and the residue was purified by silicagel column chromatography (chloroform/methanol=10/1) to obtain 6.7 mg ofthe above identified compound as colorless powder.

Rf: 0.38 (chloroform/methanol=10/1)

Mass spectrum m/z 664(M⁺ +1)

NMR (300 MHz, CDCl₃) δppm: 0.81(3H,t,J=7.6 Hz), 0.80-1.90(18H,m),2.45-2.96(12H,m), 3.02-3.76(9H,m), 4.55-4.71(2H,m), 7.28-7.63(4H,m),7.74-7.91(2H,m), 8.02(1H,d,J=8 Hz)

EXAMPLE 27 (2S,3R,4S)-4-[L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucyl]amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) Ethyl 2-isobutyl-2-propenoate

(a) 1.6 g of a sodium hydride dispersion (60% in oil) was washed threetimes with n-pentane and dried by an argon stream. The obtained powderwas suspended in 14 ml of dry DMF under an argon stream and 8.97 g ofethyl diethylphosphonoacetate was dropwise added thereto under stirringat 0° C. The mixture was stirred at room temperature for one hour andthen cooled to 0° C. Then, 6.58 g of 1-bromo-2-methylpropane wasdropwise added under stirring. Then, the mixture was stirred at 55° C.overnight. Then, 80 ml of water was added thereto, and the mixture wasextracted with ethyl acetate. The ethyl acetate layer was washed withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous sodium sulfate. Then, the solvent was distilled off. Theresidue was purified by silica gel column chromatography(n-hexane/acetone=4/1) to obtain 7.59 g of ethyl2-diethylphosphono-4-methylpentanoate as colorless oily substance.

Rf: 0.23 (n-hexane/acetone=2/1)

NMR (300 MHz, CDCl₃): δppm: 0.84-0.95(6H), 1.22-1.36(9H), 1.58(1H,m),1.86(1H,m), 1.98(1H,m), 3.02(1H,m), 4.06-4.25(6H)

(b) 333 mg of lithium chloride was suspended in 14 ml of dry THF. Then,2.0 g of ethyl 2-diethylphosphono-4-methylpentanoate was added theretounder stirring. Then, 1.41 g of DBU was added thereto in the form of adry THF solution. Then, a suspension of 348 mg of paraformaldehyde indry THF was added thereto. The mixture was stirred at room temperatureovernight. The reaction solution was subjected to filtration, and thecollected substance was washed with a small amount of benzene. Thefiltrate and the washing solution were put together and concentratedunder reduced pressure. The syrup thereby obtained was dissolved in 60ml of ethyl acetate. The ethyl acetate layer was washed with water andwith a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. Then, solvent was distilled off to obtain 700mg of ethyl 2-isobutyl-2-propenoate as colorless oily substance.

Rf: 0.53 (n-hexane/ethyl acetate=20/1)

NMR (300 MHz, CDCl₃): δppm: 0.89(6H), 1.30(3H), 1.78(1H,m), 2.17(2H,m),4.18(2H,m), 5.47(1H,s), 6.13(1H,s)

(2) L-N-[(2RS)-2-ethylthiomethyl-4-methylpentanoyl]norleucine tert-butylester

(a) 650 mg of ethyl 2-isobutyl-2-propenoate was dissolved in 3 ml ofmethylmercaptan, and 50 mg of potassium tert-butoxide was added thereto.The mixture was stirred at room temperature for two hours. The reactionsolution was diluted with 60 ml of ethyl acetate, washed with water andthen with a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The solvent was distilled off under reducedpressure to obtain 660 mg of ethyl 2-ethylthiomethyl-4-methylpentanoateas colorless oily substance.

Rf: 0.40 (n-hexane/ethyl acetate=20/1)

NMR (300 MHz, CDCl₃) δppm: 0.90(6H), 1.20-1.34(6H), 1.48-1.68(2H),1.75(0.5H), 2.00(0.5H), 2.52(2H), 2.59-2.79(3H), 4.15(2H)

(b) 650 mg of ethyl 2-ethylthiomethyl-4-methylpentanoate was dissolvedin 6 ml of an ethanol/water (10/1) solution, 8.9 ml of an ethanol/water(10/1) solution of 2N potassium hydroxide was added thereto. Thesolution was stirred at room temperature for 2.5 hours, and then, thereaction solution was distilled off under reduced pressure to obtain asuspension. To this suspension, 40 ml of water was added, and thereaction solution was adjusted to pH2 with 2N hydrochloric acid undercooling with ice, and extracted with ethyl acetate. The ethyl acetatelayer was washed with water and then with a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. Then, thesolvent was distilled off to obtain 577 mg of2-ethylthiomethyl-4-methylpentanoic acid as colorless oily substance.

Rf: 0.41 (chloroform/methanol/acetic acid=10/0.5/0.1)

(c) 570 mg of 2-ethylthiomethyl-4-methylpentanoic acid was dissolved in7 ml of dry DMF, and 618 mg of L-norleucine tert-butyl ester, 657 mg of1-hydroxybenzotriazole and 860 mg of DCC were added thereto at 0° C.under stirring. The mixture was stirred at room temperature overnight.Then, the precipitated dicyclohexyl urea was removed by filtration. Thefiltrate was diluted with 100 ml of ethyl acetate. The ethyl acetatelayer was washed sequentially with 10% citric acid aqueous solution,with water, with a 4% sodium hydrogencarbonate aqueous solution, withwater, with a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The solvent was distilled off. A small amountof chloroform was added to the residue, the insolubles were removedtwice by filtration. The filtrate thereby obtained was distilled offunder reduced pressure. The residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=20/1) to obtain 679 mg ofL-N-[(2RS)-2-ethylthiomethyl-4-methylpentanoyl]-norleucine tert-butylester.

Rf: 0.35 (n-hexane/ethyl acetate=5/1)

NMR (300 MHz, CDCl₃) δppm: 0.8(9H), 1.19-1.43(7H), 1.46(9H)1.52-1.73(4H), 1.82(1H), 2.37(1H) 2.45-2.63(3H), 2.78(1H), 4.50(1H)6.08(0.5H), 6.16(0.5H)

(b 3) (2S,3R,4S)-4-[L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucyl]amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 679 mg of L-N-[(2RS)-2-ehtylthiomethyl-4-methylpentanoyl]norleucinetert-butyl ester was dissolved in 10 ml of methanol, and 3.21 ml of a30% hydrogen peroxide aqueous solution and 62.4 mg of sodium tungstatedehydrate were added thereto. The mixture was stirred at roomtemperature for 2 hours. Then, 42 mg of sodium tungstate dehydrate wasfurther added thereto, and the mixture was stirred at room temperaturefor 4 hours. 100 ml of ethyl acetate was added to the reaction solution,and the ethyl acetate layer was washed with water and with a sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Thesolvent was distilled off, and the residue thereby obtained was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=3/1) toobtain 358 mg of the isomer having a high Rf value ofL-N-(2-ethylsulfonylmethyl-4-methylpentanoyl)norleucine tert-butyl esterand 315 mg of the isomer having a low Rf value.

Isomer having a high Rf value:

Rf: 0.66 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 0.85-1.00(9H), 1.20-1.40(7H), 1.46(9H,s),1.53-1.73(4H), 1.80(1H,m), 2.79-3.06(4H), 3.57(1H,dd,J=8,15 Hz),4.40(1H,dt,J=7,8 Hz), 6.27(1H,d,J=8 Hz)

Isomer having a low Rf value:

Rf: 0.56 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 0.85-1.00(9H), 1.22-1.42(7H), 1.47(9H,s),1.52-1.88(5H), 2.80-3.02(4H), 3.60(1H,m), 4.46(1H,m), 6..16(1H,d,J=8 Hz)

(b) 358 mg of the isomer having a high Rf value of L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucine tert-butyl esterwas dissolved in dry dichloromethane, and 1.5 ml of TFA was addedthereto. The reaction solution was stirred at room temperature for 1.5hours, and then concentrated under reduced pressure to obtain a syrup.The syrup was dissolved in benzene, and the solution was concentratedunder reduced pressure. This operation was repeated. The syrup wascrystallized from diethyl ether/n-hexane, and evaporated under reducedpressure to dryness to obtain 312 mg of L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucine as colorlesssolid.

Rf: 0.24 (chloroform/methanol/acetic acid=10/0.5/0.1)

NMR (300 MHz, CDCl₃): δppm: 0.85-1.00(9H), 1.20-1.45(8H), 1.51-1.83(3H),1.93(1H,m), 2.82-3.17(4H), 3.62(1H,dd,J=8,15 Hz), 4.56(1H,dt,J=7,8HZ),6.91(1H,br)

(c) 25.6 mg of L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucine was dissolved in0.5 ml of dry DMF, and a dry DMF solution of 30.8 mg of triethylamine,25.2 mg of DPPA and 38.5 mg of(2RS,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was added thereto at -15° C. under stirring. The mixturewas stirred at the same temperature for one hour and at room temperatureovernight. The reaction solution was diluted with 10 ml of ethylacetate. The ethyl acetate layer was washed with water and with asaturated sodium chloride aqueous solution and dried over anhydroussodium sulfate. The solvent was distilled off under reduced pressure,and the residue thereby obtained was purified silica gel columnchromatography (chloroform/methanol=50/1) to obtain 21.7 mg of(2S,3R,4S)-4-{L-N-[(2S orR)-2-ethylsulfonylmethyl-4-methylpentanoyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solid.

Rf: 0.51 (chloroform/methanol=10/1)

Mass spectrum m/z 604(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.85-1.02(9H), 1.08-1.98(25H), 2.46(2H,br),2.62(1H,t,J=11 Hz), 2.72-3.06(5H), 3.24(2H,m), 3.38-3.52(2H,m),3.52-3.77(5H), 4.24(2H,m), 4.90(1H,br), 6.18(1H,d,J=7.1 Hz)7.12(1H,d,J=8.7 Hz)

EXAMPLE 28 (2S,3R,4S)-4-{L-N-[(2S orR)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

50.5 mg of L-N-[(2S orR)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine was dissolved in0.5 ml of dry DMF, and a dry DMF solution of 58.2 mg of triethylamine,47.4 mg of DPPA and 72.3 mg of(2RS,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was added thereto at -15° C. under stirring. The mixturewas stirred at the same temperature for two hours and at roomtemperature overnight. The reaction solution was diluted with 30 ml ofethyl acetate, and the ethyl acetate layer was washed with water andwtih a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The solvent was distilled off, and the residuethereby obtained was purified by silica gel column chromatography(chloroform/methanol=100/1) to obtain 25.5 mg of the above identifiedcompound as colorless solid.

Rf: 0.50 (chloroform/methanol=20/1)

NMR (300 MHz, CDCl₃): δppm: 0.75-1.04(5H), 1.04-1.35(11H),1.35-1.80(12H), 1.85(1H,m), 2.38-2.68(8H), 2.78(2H), 3.25(2H,d,J=7.9Hz), 3.48(2H,m), 3.68(4H), 4.22(2H,m), 4.58(1H,br), 5.55(1H,d,J=7.1 Hz),5.90(1H,d,J=8.7 Hz), 7.38(2H,m), 7.54(2H,m), 7.75(1H,d,J=7.9 Hz),7.88(1H,d,J=7.9 Hz), 7.96(1H,d,J=7.9 Hz)

EXAMPLE 29 (2S,3R,4S)-4-{L-N-[(2S orR)-5-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

90 mg of L-N-[(2S orR)-S-ethylsulfonyl-2-(1-naphthylmethyl)pentanoyl]norleucine wasdissolved in 0.4 ml of dry DMF, and 81.4 mg of triethylamine, 66.3 mg ofDPPA and 0.4 ml of a dry DMF solution of 101 mg of(2RS,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was added thereto at -15° C. under stirring. The mixturewas stirred at the same temperature for 2 hours and at room temperatureovernight. The reaction solution was diluted with 50 ml of ethylacetate, and the ethyl acetate layer was washed with water and with asaturated sodium chloride aqueous solution and dried over anhydroussodium sulfate. The solvent was distilled off, and the residue waspurified by silica gel column chromatography (chloroform/methanol=50/1)to obtain 46.2 mg of the above identified compound as colorless solid.

Rf: 0.51 (chloroform/methanol=10/1)

NMR (300 MHz, CDCl₃): δppm: 0.76-1.05(5H), 1.05-2.02(24H), 2.48(2H,m),2.62(2H,m), 2.70-3.00(6H), 3.22(1H,m), 3.32(1H,m), 3.48(2H,m), 3.65(4H),4.22(2H,m), 4.60(1H,br), 5.84(1H,d,J=7.1 Hz), 5.96(1H,d,J=8.7 Hz),7.38(2H,m), 7.54(2H,m), 7.76(1H,d,J=7.9 Hz), 7.88(1H,d,J=7,9 Hz),7.98(1H,d,J=7.9 Hz)

EXAMPLE 30(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]norluecyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

The condensation reaction was conducted by using 33 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(8-quinolylmethyl)propionyl]norleucine whichwas one of diastereomers, as an acid component, and 1 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride, 51 μl of triethylamine and 21 μl of DPPA as aminecomponents. The product was purified by silica gel column chromatography(chloroform/methanol/conc. ammonia=150/3/0.1) to obtain 27 mg of theabove identified compound.

Rf: 0.48 (chloroform/methanol=10/1)

EXAMPLE 31 (2S,3R,4S)-4-{L-N.sup.α-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 56.5 mg of L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl)-N^(im)-triphenylmethylhistidine was dissolved in 0.4 ml of dry DMF, 10.4 mg oftriethylamine and 28.3 mg of DPPA were added thereto at -15° C. understirring. Further, 24.3 mg of triethylamine and 43.1 mg of(2RS,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol.dihydrochloridewere added thereto, and the mixture was stirred at the same temperaturefor 1 hour and at room temperature overnight. The reaction solution wasdiluted with 30 ml of ethyl acetate, and the ethyl acetate layer waswashed with water and with a saturated sodium chloride aqueous solutionand dried over anhydrous sodium sulfate. Then, the solvent was distilledoff. The residue was purified by silica gel column chromatography(chloroform/methanol=40/1) to obtain 32.3 mg of (2S,3R,4S)-4-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol as colorless solid.

Rf: 0.45, 0.53 (chloroform/methanol=10/1)

Mass spectrum m/z 954(M⁺ +1)

(b) 32.3 mg of (2S,3R,4S)-4-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolwas dissolved in 0.4 ml of dichloromethane, and 0.1 ml of TFA was addedthereto. The mixture was stirred at room temperature for one hour, andthen the solvent was distilled off. The residue was dissolved in 15 mlof ethyl acetate, and the organic layer was washed sequentially with a4% sodium hydrogencarbonate aqueous solution, with water and with asaturated sodium chloride aqueous solution and dried over anhydroussodium sulfate. The solvent was distilled off, and the residue therebyobtained was purified by silica gel column chromatography(toluene/methanol=10/1) to obtain 19.1 mg of (2S,3R,4S)-4-{L-N.sup.α-[(2RS)-3-ethylsulfonyl]-2-(1-naphthylmethyl)pentanoyl]histidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solid.

Rf: 0.07, 0.17 (chloroform/methanol=10/1)

Mass spectrum m/z 712(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.62-1.87(16H), 2.48(2H), 2.55-2.95(5H),3.05(4H,m), 3.25-3.58(5H), 3.58-3.80(5H), 4.10(0.7H,m), 4.19(0.3H,m),4.43(0.7H,m), 4.53(0.3H,m), 6.88(0.3H,s), 6.91(0.7H,s), 7.30-7.65(5H),7.76(1H), 7.87(1H), 8.04(1H)

(c) 16 mg of (2S,3R,4S)-4-{L-N.sup.α-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolwas purified by high performance liquid chromatography (Inertsil, ODS,7.6×250 mm) by using a solvent mixture of 0.01M phospholicacid-triethylamine bufer (pH7)-methanol (30-70) to obtain 2.45 mg of(2S,3R,4S)-4-{L-N.sup.α-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionylhistidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solid.

Retention time: 29.30 minutes

Column: Inertsil ODS 7.6×250 mm

Moving phase: 0.01M phospholic acid-triethylamine (pH7)/methanol=30/70

Verosity: 2.5 ml/min.

Detector: UV (245 nm)

EXAMPLE 32(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]seryl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]serine

(a) 72.5 mg of (2RS)-3-ethylthio-2-(1-naphthylmethyl)propionic acid wasdissolved in 0.2 ml of dry DMF, and 99 μl of triethylamine 77 μl of OPPAand 0.6 ml of a dry DMF solution of 60.4 mg of L-serine ethyl esterhydrochloride was added thereto at -15° C. under stirring. The mixturewas stirred at room temperature overnight. Then, 50 ml of ethyl acetatewas added to the reaction solution, and the mixture was washed withwater and with a saturated sodium chloride aqueous solution. The ethylacetate layer was dried over anhydrous magnesium sulfate, and then thesolvent was distilled off under reduced pressure. The residue waspurified by silica gel column chromatography (n-hexane/ethylacetate=2/1) to obtain 28.8 mg ofL-N-{(2S)-3-ethylthio-2-(1-naphthylmethyl)propionyl}serine ethyl esteras colorless powder.

Rf: 0.32 (n-hexane/ethyl acetate=1/1)

(b) 28.8 mg ofL-N-{(2S)-3-ethylthio-2-(1-naphthylmethyl)propionyl}serine ethyl esterwas dissolved in 0.4 ml of ethanol, and 0.34 ml of an ethanol/water(10/1) solution of 1N potassium hydroxide was added thereto. The mixturewas stirred at room temperature for 1.5 hours. Under cooling with ice,1N hydrochloric acid was added to the reaction solution to adjust thesolution to pH2, and the solution was extracted with ethyl acetate. Theethyl acetate layer was washed with water and with a saturated sodiumchloride aqueous solution and dried over anhydrous magnesium sulfate.Then, the solvent was distilled off under reduced pressure to obtain26.1 mg of L-N-{(2S)-3-ethylthio-2-(1-naphthylmethyl)propionyl}serine ascolorless oily substance.

Rf: 0.23 (chloroform/methanol/acetic acid=10/1/0.2)

(c) 26.1 mg ofL-N-{(2S)-3-ethylthio-2-(1-naphthylmethyl)propionyl}serine was dissolvedin 0.8 ml of methanol, and 0.14 ml of a 30% hydrogen peroxide aqueoussolution and 2.6 mg of sodium tungstate dehydrate were added thereto.The mixture was stirred at room temperature for 5.5 hours. 30 ml ofethyl acetate was added to the reaction solution, and the mixture waswashed sequentially with 1N hydrochloric acid, with water and with asaturated sodium chloride aqueous solution. The ethyl acetate layer wasdried over anhydrous magnesium sulfate, and the solvent was distilledoff under reduced pressure to obtain 28.3 mg ofL-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}serine ascolorless oily substance.

Rf: 0.08 (chloroform/methanol/acetic acid=10/1/0.2)

(2) (2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]seryl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

28.3 mg ofL-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]serine wasdissolved in 0.1 ml of dry DMF, and 44 μl of triethylamine, 22 μl ofDPPA and 0.3 ml of a dry DMF solution of 38.1 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was added thereto at -15° C. under stirring. The mixturewas stirred at room temperature overnight. Then, 35 ml of ethyl acetatewas added to the reaction solution, and the mixture was washed withwater and with a saturated sodium chloride aqueous solution. The ethylacetate layer was dried over anhydrous magnesium sulfate, and thesolvent was distilled off under reduced pressure. The residue waspurified by silica gel column chromatography (chloroform/methanol=30/1)to obtain 11.5 mg of the above identified compound as colorless powder.

Rf: 0.24 (chloroform/methanol=10/1)

Mass spectrum m/z 662(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.70-0.98(3H,m), 1.23(3H,t,J=7.6 Hz),1.04-1.80(13H,m), 2.43-2.67(2H,m), 2.68-2.90(4H,m), 2.93-3.21(4H,m),3.30-3.52(5H,m), 3.58-3.81(6H,m), 4.10-4.27(2H,m), 4.77(1H,br s),6.08(1H,d,J=8 Hz), 6.96(1H,d,J=9 Hz), 7.28-7.63(4H,m), 7.79(1H,d,J=8Hz), 7.89(1H,d,J=8 Hz), 7.99(1H,d,J=8 Hz)

EXAMPLE 33(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]methionyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-N-[(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]methionine

(a) 1.0 g of (2RS)-3-ethylthio-2-(1-naphthylmethyl)propionic acid wasdissolved in 36 ml of methanol, and 6.1 ml of a 30% hydrogen peroxideaqueous solution and 140 mg of sodium tungstate dehydrate were addedthereto. The mixture was stirred at room temperature overnight. 350 mlof ethyl acetate was added to the reaction solution, and the mixture waswashed sequentially with 1N hydrochloric acid, with water and with asaturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressureto obtain 1.08 g of (2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionicacid as colorless crystals.

Rf: 0.47 (chloroform/methanol/acetic acid=10/1/0.5)

(b) 99.2 mg of L-methionine ethyl ester monohydrochloride was dissolvedin 1.5 ml of dichloromethane, and 65 μl of triethylamine was addedthereto. Under cooling with ice, 129.9 mg of(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionic acid, 71.5 mg of1-hydroxybenzotriazole and 99.5 mg of DCC were added thereto. Themixture was stirred at room temperature overnight, and then, theinsolubles substances were removed by filtration. The filtrate wasdiluted with ethyl acetate, washed sequentially with a 10% citric acidaqueous solution, with a saturated sodium carbonate aqueous solution andwith a saturated sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure, and the residue was purified by silica gel columnchromatography (chloroform/ethyl acetate=3/1) to obtain 51.3 mg ofL-N-{(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}methionineethyl ester as colorless powder.

Rf: 0.38, 0.45 (chloroform/ethyl acetate=5/1)

(c) 80 mg ofL-N-{(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}methionine wasdissolved in 3.6 ml of ethanol, and 0.86 ml of an ethanol/water (10/1)solution of 1N potassium hydroxide was added thereto. The mixture waswashed with water and with a saturated sodium chloride aqueous solution.The ethyl acetate layer was dried over anhydrous magnesium sulfate, andthe solvent was distilled off under reduced pressure to obtain 75.3 mgof L-N-{(2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}methionineas colorless crystals.

Rf: 0.31, 0.43 (chloroform/methanol/acetic acid=10/1/0.5)

(2)(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]methionyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

75.3 mg of the compound obtained in step (1) was dissolved in 0.5 ml ofdry DMF, and 106 μl of triethylamine, 56 μl of DPPA and 90.4 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol.dihydrochloridewere added thereto at -15° C. under stirring. The mixture was stirred atroom temperature overnight. Ethyl acetate was added to the reactionsolution, and the mixture was washed with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. The residue was purified by silica gel column chromatography(chloroform/methanol=20/1), and separated and purificated by thin layerchromatography (silica gel plate, developer: chloroform/methanol=10/1)to obtain 12.6 mg of the above identified compound as colorless powder.

Rf: 0.41 (chloroform/methanol=10/1)

Mass spectrum m/z 706(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.80-1.06(2H,m), 1.06-2.10(16H,m),2.03(3H,s), 2.40-2.90(10H,m), 3.02(1H,dd,J=3,14 Hz), 3.24-3.78(12H,m),4.15-4.32(1H,m), 4.39-4.55(1H,m), 6.23(1H,d,J=9 Hz), 6.50(1H,d,J=6 Hz),7.29-7.63(4H,m), 7.79(1H,d,J=8 Hz), 7.89(1H,d,J=8 Hz, 8.00(1H,d,J=8 Hz)

EXAMPLE 34(2S,3R,4S)-4-{L-N-[(2S)-3-isopropylsulfonyl-2-(8-quinolylmethyl)propionyl]leucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) The ethyl ester of the above identified compound was obtained in thesame manner as in Example 10 by Michael addition reaction of ethyl2-(8-quinolylmethyl)acrylate with isopropylmercaptan. The ester wassubjected to saponification by an ethanol/water (10/1) solution of 1Npotassium hydroxide, and then3-isopropylthio-2-(8-quinolylmethyl)propionic acid as yellow solid(yield: 81%).

NMR (300 MHz, CDCl₃): δppm: 1.16(3H,d,J=7 Hz), 1.23(3H,d,J=7 Hz),2.75(1H,m), 2.8-2.9(2H,m), 3.18(2H,m), 3.87(1H,dd,J=2.4,15 Hz)

(b) (2RS)-3-isopropylthio-2-(8-quinolylmethyl)propionic acid withleucine tert-butyl ester were condensed by a usual DPPA method, followedby oxidation into the sulfonyl compound in methanol/30% hydrogenperoxide aqueous solution (10/1) in the presence of a sidium tungstatecatalyst. The product was purified by. silica gel column chromatography(n-hexane/ethyl acetate=1/1) to obtainL-N-[(2RS)-3-isopropylsulfonyl-2-(8-quinolylmethyl)propionyl]leucinetert-butyl ester as colorless transparent syrup.

Rf: 0.27, 0.30 (n-hexane/ethyl acetate=1/1)

(c) 54 mg ofL-N-[(2RS)-3-isopropylsulfonyl-2-(8-quinolylmethyl)propionyl]leucinetert-butyl ester was dissolved in 0.8 ml of dichloromethane/TFA (1/1).The solution was concentrated under reduced pressure and dried to obtain45 mg ofL-N-[(2RS)-3-isopropylsulfonyl-2-(8-quinolylmethyl)propionyl]leucine assolid. This compound was subjected to condensation reaction with(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol by a usualDPPA method. The product was purified by silica gel columnchromatography (chloroform/methanol=50/1) and separated a stereoisomerto obtain 17 mg of the above-identified compound.

Rf: 0.46 (chloroform/methanol=50/1)

EXAMPLE 35 (2S,3R,4S)-4-{L-N.sup.α-[(2S)-3-isopropylsulfinyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 7 g of sodium hydroxide was dissolved in 30 ml of water. 45 ml ofmethanol was added thereto and throughly mixed therewith, and 6.86 ml ofβ-mercaptopropionic acid was dropwise added thereto. Then, 17.43 g ofisopropyl bromide was added thereto, and the mixture was stirred at roomtemperature overnight. The isopropyl bromide was gradually dissolved andreacted. The reaction solution was diluted with 120 ml of water andwashed with 120 ml of diethyl ether. The separated aqueous layer wasadjusted to pH1 with conc. hydrochloric acid under cooling with ice, andextracted with ethyl acetate (200 ml×2, 100×1). Then, the organic layerwas washed with a saturated sodium chloride aqueous solution (100 ml×2),dried over anhydrous magnesium sulfate, and then concentrated underreduced pressure to obtain 9.27 g of syrup of 3-isopropylthiopropionicacid.

Rf: 0.43 (chloroform/methanol/33% acetic acid=10/1/0.5)

(b) 226 mg of 3-isopropylthiopropionic acid was dissolved in 1.5 ml ofdry dichloromethane. 0.22 ml (L.0 eq) of triethylamine was addedthereto, and then the mixture was cooled with ice. 0.19 ml of pivaloylchloride was added thereto under stirring to obtain a gelled reactionsolution. The reaction solution was stirred at 10° C. for 10 minutes andthen cooled with ice. A dichloromethane solution of lithium amideprepared from 270 mg of (4R,5S)-4-methyl-5-phenyl-2-oxazolidinone and0.96 ml of 1.5M n-butyl lithium was prepared, and the solution was addedto the previous reaction solution under cooling with ice. The mixturewas stirred at room temperature overnight, and then the reactionsolution was diluted with 20 ml of chloroform. After washing with 15 mlof a 4% sodium hydrogencarbonate aqueous solution, the chloroformsolution was dried over anhydrous magnesium sulfate. The chloroformsolution was concentrated under reduced pressure, and then purified bysilica gel column chromatography (n-hexane/ethyl acetate=6/1) to obtain240 mg of(4R,5S)-3-(3-isopropylthiopropionyi)-4-methyl-5-phenyl-2-oxazolidinoneas colorless transparent syrup (yield: 51%).

(c) 4.47 g of(4R,5S)-3-(3-isopropylthiopropionyl)-4-methyl-5-phenyl-2-oxazolidinonewas dissolved in 30 ml of dry THF. 24 ml of tetrahydrofuran solution oflithium diisopropylamide prepared from 2.36 g of diisopropylamine, 20 mlof THF and 14.7 ml of a n-hexane solution of 15% n-butyl lithium, wasadded thereto at -78° C. The mixture was stirred at -78° C. for 30minutes. 15 ml of a THF solution of 3.57 g of 1-(bromomethyl)naphthalenewas dropwise added thereto. Then, temperature of the reaction solutionwas raised to -35° C., and the stirring was continued overnight. 40 mlof a saturated ammonium chloride aqueous solution was added to thereaction solution to decompose excess anions in the reaction solution.Further, the reaction solution was diluted with 40 ml of water andextracted with 200 ml of ethyl acetate. The ethyl acetate layer waswashed sequentially with 100 ml of a 5% potassium hydrogen sulfateaqueous solution, with 100 ml of a 4% sodium hydrogencarbonate aqueoussolution and with 100 ml of a saturated sodium chloride aqueoussolution. The ethyl acetate layer was dried over anydrous sodiumsulfate, and then concentrated under reduced pressure. The resultingsyrup was purified by silica gel column chromatography (n-hexane/ethylacetate=7/1) to obtain 1.78 g of(4R,5S)-3-{(2S)-3-isopropylthio-2-(1-naphthylmethyl)propionyl}-4-methyl-5-phenyl-2-oxazolidinoneas slightly yellow transparent syrup (yield: 27%).

NMR (300 MHz, CDCl₃): δppm: 0.65(3H,d,J=7.1 Hz), 1.14(3H,d,J=6.6 Hz),1.20(3H,d,J=6.5HZ), 2.63(1H,dd,J=5.7,12.6 Hz), 2.92(1H,m),2.95(1H,dd,J=8.9,12.6 Hz), 3.41(1H,dd,J=9.9,13.8 Hz),3.54(1H,dd,J=4.7,13.8 Hz), 4.70(1H,m), 4.77(1H,m), 5.62(1H,d,J=7.0 Hz)

Optical purity: 99% (HPLC analysis)

(d) 45 mg of(4R,5S)-3-{(2S)-3-isopropylthio-2-(1-naphthylmethyl)propionyl}-4-methyl-5-phenyl-2-oxazolidinonewas dissolved in 0.6 ml of THF. 0.3 ml of a solution of 50 mg/ml lithiumhydroxide monohydrate was added thereto under cooling with ice. Themixture was stirred at 0° C. for 1 hour and at room temperature for 3hours. Only the THF was concentrated under reduced pressure, and waterwas added thereto. Then, the precipitated norephedrineamide was removedby filtration. The filtrate was adjusted to pH1 with 1N hydrochloricacid, and extracted with ethyl acetate (15 ml×2 times). The ethylacetate layer was dried over anhydrous magnesium sulfate, and thenconcentrated under reduced pressure to obtain 24 mg (yield: 24%) of asyrup of (2S)-3-isopropylthio-2-(1-naphthylmethyl)propionic acid. Thiscompound was condensed with L-N^(im) -triphenylmethylhistidine methylester by a usual DPPA method. The product was purified to obtain 40 mgof L-N.sup.α-[(2S)-3-isopropylthio-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine methyl ester as white solid.

Rf: 0.36 (benzene/methanol=20/1)

(e) 40 mg of L-N.sup.α-[(2S)-3-isopropylthio-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine methyl ester was dissolved in 0.6 ml ofdioxane. 0.3 ml of a 37 mg/ml sodium bromide trihydrate aqueous solutionwas added thereto at room temperature. The reaction solution was stirredat room temperature for 15 minutes, and then diluted with 20 ml of ethylacetate. The reaction solution was washed with 8 ml of water and thenwith 8 ml of a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. The reaction solution was concentrated underreduced pressure to obtain yellow solid. This product was saponifiedwith a solution of 0.4N potassium hydroxide in methanol/water (10/1) toobtain 40 mg of L-N.sup.α-[(2S)-3-isopropylsulfinyl-2-(1-naphthylmethyl)propionyl]-N^(im)-triphenylmethylhistidine (Rf: 0.48, chloroform/methanol/33% aceticacid=10/1/0.2). This compound was condensed in the same manner as inExample 11 with(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol by a usualDPPA method, further subjected to removal of a triphenylmethyl group bydichloromethane/TFA (3/4). The product was purified by silica gel columnchromatography (chloroform/methanol/conc. aqueous ammonia=30/3/0.02) toobtain 20 mg of (2S,3R,4S)-4-{L-N.sup.α-[(2S)-3-isopropylsulfinyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-5-cyclohexyl-i-morpholino-2,3-pentanediolas white solid.

Rf: 0.28, 0.27 (chloroform/methanol/conc. aqueous ammonia=10/1/0.5)

EXAMPLE 36 (2S,3R,4S)-4-{L-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) (2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionic acid

(a) 3.2 g of a sodium hydride dispersion (60% in oil) was washed threetimes with n-pentane and dried in an argon stream. The resulting powderwas suspended in 30 ml of dry DMF under an argon stream, and 17.9 g ofethyl diethylphosphono acetate was dropwise added thereto over a periodof 1 hour at 0° C. under stirring. The mixture was stirred at roomtemperature for 1 hour and cooled to 0° C. 17.0 g of1-chloromethylnaphthalene was dropwise added thereto over a period of 50minutes under stirring. The mixture was stirred at 55° C. overnight.Then, 160 ml of water was added to the reaction solution, and themixture was extracted with ethyl acetate (80 ml×3 times). The ethylacetate layer was washed with a saturated sodium chloride aqueoussolution and dried over anhydrous sodium sulfate. The solvent wasdistilled off, and the syrup thereby obtained was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=2/3) to obtain 28.7 g ofethyl 2-diethylphosphono-3-(1-naphthyl)propionate as colorless oilysubstance.

Rf: 0.37 (n-hexane/ethyl acetate=1/2)

(b) 1.92 g of lithium chloride was sun-pended in 50 ml of dry THF, and15 g of ethyl 2-diethylphosphono-3-(1-naphthyl)propionate was dropwiseadded thereto. Then, 16 ml of a 50% dry THF solution of DBU was dropwiseadded thereto, and 2.01 g of paraformaldehyde suspended in dry THF wasadded thereto. The mixture was stirred at room temperature for 3 hours,and the insolubles were removed by filtration and washed with a smallamount of diethyl ether. The washing solution and and the filtrate wereput together, and the solvent was distilled off. The resulting syrup wasdissolved in 180+ml of diethyl ether. The diethyl ether layer was washedsequentially with a 10% citric acid aqueous solution, with water andwith a saturated sodium chloride aqueous solution and dried overanhydride sodium sulfate. The solvent was distilled off, and the syrupthereby obtained was purified by silica gel column chromatography(n-hexane/diethyl ether=20/1) to obtain 6.48 g of ethyl2-(1-naphthyl)methyl-2-propenoate as colorless oily substance.

Rf: 0.45 (n-hexane/ethyl acetate=10/1)

NMR (300 MHz, CDCl₃): δppm: 1.33(3H,t,J=6,9 Hz), 4.10(2H,s),4.27(2H,q,J=6.9 Hz), 5.16(1H,d,J=1.5 Hz), 6.24(1H,d,J=1.5 Hz),7.35(1H,d,J=8 Hz), 7.40-7.52(3H), 7.78(2H,d,J=8 Hz), 7.82-7.95(2H)

(c) 2.04 g of ethyl 2-(1-naphthyl)methyl-2-propenoate was dissolved in714 μl of 2-mercaptoethanol, and 102 mg of potassium tert-butoxide wasadded thereto at room temperature under stirring. The mixture wasstirred at room temperature for 15 minutes. 500 μl of 2-mercaptoethanolwas added thereto and the mixture was stirred for 15 minutes. Then, thereaction solution was diluted with 150 ml of diethyl ether. The diethylether layer was washed with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. The solventwas distilled off to obtain 2.81 g of ethyl(2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionate as colorlessoily substance.

Rf: 0.43 (n-hexane/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 1.08(3H,t,J=7.5 Hz), 2.40(1H,br),2.63(2H,t,J=5.9 Hz), 2.69(1H,m), 2.84(1H,m), 3.04(1H,m), 3.35(2H,m),3.61(2H,t,J=5.9 Hz), 4.04(2H,q,J=7.5 Hz), 7.30(2H,m), 7.48(2H,m),7.70(1H,d,J=7.9 Hz), 7.82(1H,d,J=7.9 Hz), 8.00(1H,d,J=7.9 Hz)

(d) 151 mg of ethyl(2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionate wasdissolved in 0.9 ml of a solution of ethanol/water (10/1), and 1.18 mlof a solution of 2N potassium hydroxide in ethanol/water (10/1) wasadded thereto. The mixture was stirred at room temperature for 2 hours,and then the reaction solution was concentrated under reduced pressure.To the concentrated solution, water was added and the reaction solutionwas adujusted to pH2 with 2N hydrochloric acid at 0° C under stirring,and extracted with ethyl acetate. The ethyl acetate layer was washedwith water and with a saturated sodium chloride aqueous solution anddried over anhydrous sodium sulfate. Then, the solvent was distilledoff, and the residue thereby obtained was purified by silica gel columnchromatography (chloroform/ethyl acetate/acetic acid=6/3/0.1) to obtain82 mg of (2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionate ascolorless solid.

Rf: 0.28 (chloroform/methanol/acetic acid=10/0.5/0.1)

NMR (300 MHz, CDCl₃): δppm: 2.68(2H,t,J=5.7 Hz), 2.74(1H,m), 2.86(1H,m),3.14(1H,m), 3.33(1H,dd,J=6.3,13.8 Hz), 3.57(1H,dd,J=6.3,13.8 Hz),3.64(2H,t,J=5.7 Hz), 7.38(2H,m), 7.52(2H,m), 7.77(1H,d,J=7.2 Hz),7.88(1H,dd,J=1.8,7.8 Hz), 8.60(1H,d,J=8.4 Hz)

(2) (2S,3R,4S)-4-{L-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 80 mg of (2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionicacid was dissolved in 0.7 ml of dry DMF. 56.9 mg of L-norleucinetert-butyl ester, 68.6 mg of 1-hydroxybenzotriazole and 79.2 mg of DCCwere added thereto at 0° C. under stirring. The mixture was stirred atroom temperature overnight. The precipitated dicyclohexyl urea wasremoved by filtration, and the filtrate was diluted with 20 ml of ethylacetate. The ethyl acetate layer was washed sequentially with a 10%citric acid aqueous solution, with water and with a saturated sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Then,the solvent was distilled off, and the residue was purified by silicagel column chromatography (chloroform/ethyl acetate=7/1) to obtain 35.7mg of the isomer having a high Rf value ofL-N-[(2RS)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester, and 15.9 mg of the isomer having a low Rf value and32.3 mg of the mixture thereof.

Isomer having a high Rf value:

Rf: 0.60 (chloroform/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 0.85(3H,t,J=7.1 Hz), 1.00-2.00(15H),2.64(2H,t,J=5.1 Hz), 2.68-2.84(3H), 2.96(1H,m), 3.32(2H,m),3.66(2H,d,J=5.1 Hz), 4.35(1H,m), 6.10(1H,d,J=7.9 Hz), 7.26-7.40(2H)7.44-7.60(2H), 7.72(1H,d,J=7.9 Hz), 7.84(1H,d,J=7.9 Hz), 8.04(1H,d,J=7.9Hz)

Isomer having a low Rf value:

Rf: 0.52 (chloroform/ethyl acetate=1/1)

(b) 359 mg of the isomer having a high Rf value ofL-N-[3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 5 ml of methanol, and 1.33 ml of a 30%hydrogen peroxide aqueous solution and 25.7 mg of sodium tungstatedehydrate were added thereto. The mixture was stirred at roomtemperature for 2 hours. The reaction solution was diluted with 50 ml ofethyl acetate, and the mixture was washed with water and with asaturated sodium chloride aqueous solution and dried over anhydroussodium sulfate. The solvent was distilled off to obtain 332 mg ofL-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester.

Rf: 0.34 (chloroform/ethyl acetate=1/1)

NMR (300 MHz, CDCl₃): δppm: 0.86(3H,t,J=7.1 Hz), 1.05-1.35(4H),1.40(9H,s), 1.54-1.82(3H), 3.02-3.24(3H), 3.24-3.50(3H), 3.92-4.06(3H),4.26(1H,m), 6.05(1H,d,J=7.9 Hz), 7.28-7.42(2H), 7.48-7.63(2H),7.76(1H,d,J=7.9 Hz), 7.88(1H,d,J=7.9 Hz), 8.01(1H,d,J=7.9 Hz)

(c) 315 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 2 ml of dry dichloromethane, and 1 mlof TFA was added thereto. The mixture was stirred at room temperaturefor three hours. The solvent was distilled off. The residue wasrecrystallized from ethyl acetate to obtain 267 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucineas colorless solid.

Rf: 0.23 (chloroform/methanol/acetic acid=10/0.5/0.1)

(d) 50 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucinewas dissolved in 0.2 ml of dry DMF, and 28.2 mg of1-hydroxybenzotriazole and 33.2 mg of DCC were added thereto at 0° C.under stirring. Then, 55.2 mg of(2RS,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was dissolved in 0.2 ml of dry DMF, and 31.1 mg oftriethylamine was added thereto for neutralization. This mixture wasadded to the previous reaction solution, and the mixture was stirred at0° C. for two hours and at room temperature overnight. The precipitateddicyclohexyl urea was removed by filtration, and the filtrate wasdiluted with 10 ml of ethyl acetate. The ethyl acetate layer was washedsequentially with a 4% sodium hydrogencarbonate aqueous solution, withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous sodium sulfate. Then, the solvent was distilled off. Theresidue was purified by silica gel column chromatography(chloroform/methanol= 20/1) to obtain 20.1 mg of (2S,3R,4S)-4-{L-N-[(2SorR)-3-(2-hydroxyethyl)sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solid.

Rf: 0.31 (chloroform/methanol=10/1)

Mass spectrum m/z 704(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.74-1.10(4H), 1.10-1.40(4H),1.40-1.82(14H), 2.50(2H), 2.58-2.83(4H), 3.09(2H,m),3.24(1H,dd,J=2.7,14.0 Hz), 3.31-3.53(6H), 3.69(4H),3.81(1H,dd,J=8.3,14.0 Hz), 3.98(2H,t,J=10.3 Hz), 4.17(1H,m),4.62(1H,br), 5.98(1H,s), 4.26(1H,m), 6.10(2H,d,J=7.9 Hz), 7.31-7.50(2H),7.50-7.65(2H), 7.81(1H,d,J=7.9 Hz), 7.91(1H,d,J=7.9 Hz), 8.02(1H,d,J=7.9Hz)

EXAMPLE 37(2S,3R,4S)-4-{L-N-[(2S)-2-benzyl-3-ethylsulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) Ethyl (2RS)-2-benzyl-3-ethylthiopropionate

(a) 2.1 g of sodium hydride (60% in oil) was suspended in DMF, and 10 gof ethyl diethylphosphonoacetate was dropwise added thereto at -20° C.under argon atmosphere. The mixture was stirred at room temperature for30 minutes, and then 9.2 g of benzyl bromide was added thereto at 0° C.The mixture was stirred at 50° C. overnight. The reaction solution waspoured into a saturated ammonium chloride aqueous solution, andextracted with ethyl acetate. The ethyl acetate layer was washed with asaturated sodium chloride aqueous solution, and then dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure. The residue was purified by silica gel column chromatography(n-hexane/acetone=6/1) to obtain 5.7 g of ethyl2-diethylphosphono-3-phenylpropionate as colorless oily substance.

Rf: 0.32 (n-hexane/acetone=3/1)

(b) 1.0 g of lithium chloride was suspended in 20 ml of THF, and 5 g ofethyl 2-diethylphosphono-3-phenylpropionate was dropwise added thereto.The mixture was stirred at room temperature for seven minutes. Then, 3.6ml of DBU was added thereto and further 11 minutes later, a suspensionof 0.72 g of paraformaldehyde in THF (20 ml) was added thereto at 0° C.The mixture was stirred at room temperature overnight. Then, the mixturewas neutralized with 1N hydrochloric acid, and water and ethyl acetatewere added thereto. The organic layer was separted, and washed with asaturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=20/1) to obtain 2.4 g of ethyl 2-benzylacrylateas colorless oily substance.

Rf: 0.54 (n-hexane,/ethyl acetate=15/1)

(c) To 1.95 g of ethyl 2-benzylacrylate, 1 ml of ethylmercaptan, and 20mg of potassium tert-butoxide was added thereto under cooling with ice.The mixture was stirred at room temperature for one hour. Then, ethylacetate was added to the reaction solution, and the mixture was washedsequentially with 1N hydrochloric acid, with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. Then, the solvent was distilled off under reduced pressure toobtain 2.5 g of the above identified compound as slightly yellow oilysubstance.

Rf: 0.32 (n-hexane/ethyl acetate=15/1)

(2) L-N-[(2RS)-2-benzyl-3-ethylsulfonylpropionyl]norleucine benzyl ester

(a) 1 g of ethyl (2RS)-2-benzyl-3-ethylthiopropionate was dissolved in 4ml of ethanol/water (9/1), and 8 ml of 2N potassium hydroxide inethanol/water (9/1) was added thereto. The mixture was stirred at roomtemperature for 4 hours. The reaction solution was neutralized with 2Nhydrochloric acid. Then, ethanol was distilled off under reducedpressure, and the residual solution was adjusted to pH2 with 2Nhydrochloric acid and extracted with ethyl acetate. The extract waswashed with water and with a saturated sodium chloride aqueous solutionand then, dried over anhydrous magnesium sulfate. The solvent wasdistilled off under reduced pressure to obtain 0.9 g of a carboxylicacid as slightly yellow oily substance.

Rf: 0.40 (benzene/methanol/acetic acid=20/1/0.5)

(b) 520 mg of the carboxylic acid obtained in step (a) and 1.0 g ofL-norleucine benzyl ester p-toluenesulfonate were dissolved in 10 ml ofDMF, and 600 μl of DPPA and 744 μl of triethylamine were added theretoat -15° C. The mixture was stirred at 0° C. for three hours and furtherat room temperature overnight. Then, ethyl acetate was added to thereaction solution, and the mixture was washed sequentially with a 4%sodium hydrogencarbonate aqueous solution, with water, with 1Nhydrochloric acid, with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. Then, thesolvent was distilled off under reduced pressure, and the residuethereby obtained was purified by silica gel column chromatography(n-hexane/ethyl acetate=6/1) to obtain 891 mg ofL-N-[(2RS)-2-benzyl-3-ethylthiopropionyl]norleucine benzyl ester ascolorless powder.

Rf: 0.31 (n-hexane/ethyl acetate=4/1)

(c) 300 mg of the L-N-acylnorleucine benzyl ester obtained in step (b)was dissolved in 10 ml of methanol, and 1 ml of a 30% hydrogen peroxideaqueous solution and 20 mg of sodium tungstate were added thereto. Themixture was stirred at room temperature overnight. The reaction solutionwas diluted with ethyl acetate, washed with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. Then, the solvent was distilled off under reduced pressure toobtain 325 mg of the above identified compound as colorless powder.

Rf: 0.23 (n-hexane/ethyl acetate=2/1)

(3)(2S,3R,4S)-4-{L-N-[(2S)-2-benzyl-3-ethylsulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 320 mg of the sulfone compound obtained in step (2) was dissolved in5 ml of ethanol, and subjected to hydrogenation at room temperatureunder an atmospheric pressure for 2 hours by an addition of palladiumblack. The catalyst was removed by filtration. Then, the filtrate wasconcentrated under reduced pressure to dryness to obtain 265 mg of acarboxylic acid as colorless powder.

Rf: 0.05, 0.14 (n-hexane/ethyl acetate/acetic acid=6/6/0.1)

(b) 100 mg of the carboxylic acid obtained in step (a), 97.3 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride and 120 mg ofbenzotriazolyl-N-hydroxytris(dimethylamino)phosphoniumhexafluorophosphate (hereinafter referred to simply as BCP reagent) weredissolved in 2 ml of DMF, and 114 μl of triethylamine was dropwise addedthereto at -10° C. The mixture was stirred at 8° C. overnight. Then,ethyl acetate was added to the reaction solution, and the mixture waswashed sequentially with a 4% sodium hydrogencarbonate aqueous solution,with water and with a sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure, and the residue was purified by silica gel columnchromatography (chloroform/methanol=60/1) to obtain 31 mg of the aboveidentified compound as colorless powder from the first fraction.Further, 75 mg of an optical isomer thereof was obtained as colorlesspowder from the second fraction.

Rf: 0.39 (chloroform/methanol 20/1)

Mass spectrum m/z 638(M⁺ +1)

EXAMPLE 38

(2S,3R,4S)-4-{L-N-[(2S)-3-tert-butylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-N-[2-(1-naphthylmethyl)acryloyl]norleucine tert-butyl ester

(a) 469 mg ofL-N-[(2R)-3-hydroxy-2-(1-naphthylmethyl)propionyl]norleucine tert-butylester was dissolved in 5 ml of dichloromethane, and 175 mg ofmethanesulfonyl chloride and 262 μl of triethylamine were dropwise addedthereto. The mixture was stirred at 8° C. overnight. Then, ethyl acetatewas added thereto, and the mixture was washed sequentially with waterand with a saturated sodium chloride aqueous solution. The organic layerwas dried over anhydrous magnesium sulfate, and then the solvent wasdistilled off under reduced pressure to obtain 566 mg ofL-N-[(2S)-3-mesyloxy-2-(1-naphthylmethyl)propionyl]norleucine tert-butylester as slightly yellow oily substance.

Rf: 0.55 (n-hexane/ethyl acetate=1/1)

(b) 22 mg of the O-mesyl compound obtained in step (a) was dissolved in0.3 ml of chloroform, and 28 μl of DBU was added thereto. The mixturewas heated at 45° C. overnight. 8.3 μl of acetic acid and ethyl acetatewere added to the reaction solution, and the mixture was washed withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous magnesium sulfate. Then, the solvent was distilled offunder reduced pressure to obtain 17.4 mg of the above identifiedcompound as slightly yellow oily substance.

Rf: 0.68 (n-hexane/ethyl acetate=2/1)

NMR (300 MHz, CDCl₃): δppm: 1.50(9H,s), 4.08(1H,d,J=17.7 Hz),4.16(1H,d,J=16.2 Hz), 4.53-4.60(1H,m), 5.01(1H,s), 5.72(1H,s)

(2)L-N-[(2S)-3-tert-butylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

(a) To 365 mg of the exo-methylene compound obtained in step (1), 1.0 mlof tert-butylmercaptan and 15 mg of potassium tert-butoxide were added,and the mixture was heated at 40° C. for 30 minutes. Ethyl acetate wasadded to the reaction solution, and the mixture was adjusted to pH6 withacetic acid. The mixture was washed with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure to obtain400 mg of.L-N-[(2RS)-3-tert-butylthio-2-(1-naphthylmethyl)propionyl]norleucine-tert-butylester as slightly yellow oily substance.

Rf: 0.35 (n-hexane/ethyl acetate=4/1)

(b) 400 mg-of the sulfide compound obtained in step (a) was dissolved in10 ml of methanol, and 1 ml of a 30% hydrogen peroxide aqueous solutionand 20 mg of sodium tungstate dehydrate were added thereto. Methanol wasdistilled off under reduced pressure for concentration. To the residualsolution, water and ethyl acetate were added, and the organic layer wasseparated. The organic layer was washed with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure to obtain373 mg of a mixture of optical isomers of a sulfone compound ascolorless solid.

The optical isomers were separated and purified by silica gel columnchromatography (n-hexane/ethyl acetate=6/1) to obtain 126 mg of theabove identified compound from the first fraction as colorless powder.

Rf: 0.37 (n-hexane/ethyl acetate=2/1)

(3)(2S,3R,4S)-4-{L-N-[(2S)-3-tert-butylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 123 mg of the sulfone compound obtained in step (2) was dissolved in2 ml of formic acid, and the solution was stirred at room temperaturefor 30 minutes. The reaction solution was concentrated underreducedpressure to dryness to obtain 116 mg of a carboxylic acid as colorlesssolid.

Rf: 0.47 (benzene/methanol/acetic acid=20/1/0.25)

(b) 30 mg of the above carboxylic acid of the above step (a), 24 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride and 30 mg of BOP reagent were dissolved in 1 ml of DMF.29 μl of triethylamine was added thereto under cooling with ice, and themixture was stirred at room temperature for 5 hours and further at 8° C.overnight. The reaction solution was diluted with ethyl acetate, washedsequentially with a 4% sodium hydrogencarbonate aqueous solution, withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous magnesium sulfate. Then, the solvent was distilled offunder reduced pressure, and the residue thereby obtained was purified bysilica gel column chromatography (chloroform/methanol=50/1) to obtain 44mg of the above identified compound as colorless powder.

Rf: 0.30 (chloroform/methanol=20/1)

Mass spectrum m/z 716(M⁺ +1)

EXAMPLE 39(2S,3R,4S)-4-[L-N-(2S)-3-[[(2S)-N-benzyloxycarbonyl-2-pyrrolidinyl]methyl]sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl]amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-N-benzyloxycarbonylprolinol

5 g of L-N-benzyloxycarbonylproline was dissolved in 100 ml of DMF, 8.1ml of ethyl iodide and 3.4 g of sodium hydrogencarbonate were addedthereto. The mixture was stirred at room temperature for 24 hours. Then,water was added to the reaction solution, and extracted with ethylacetate. The ethyl acetate layer was washed with a saturated sodiumchloride aqueous solution and dried over anhydrous magnesium sulfate.Then, the solvent was distilled off under reduced pressure. The residuethereby obtained was dissolved in a solvent mixture of 72 ml of ethanoland 48 ml of THF, and reacted at room temperature for two hours by anaddition of 2.28 g of sodium borohydride and 2.25 g of lithium chloride.3.45 ml of acetic acid was added to the reaction solution, and themixture was concentrated under reduced pressure to dryness. Water andethyl acetate were added to the residue, and the organic layer wasspeparated, washed with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. The solventwas distilled off under reduced pressure to obtain 3.57 g of the aboveidentified compound as colorless oily substance.

Rf: 0.23 (n-hexane/ethyl acetate=1/1)

(2) (2S)-2-(acetylthiomethyl)-N-benzyloxycarbonylpyrrolidine

(a) 2 g of the N-protected prolinol compound obtained in step (1) wasdissolved in 40 ml of dichloromethane, and 870 μl of methane sulfonylchloride and 1.9 ml of triethylamine were added thereto at 0° C. Themixture was stirred at room temperature for 1 hour. Then, the reactionsolution was poured into water, and the organic layer was separated. Theorganic layer was washed with water and with a saturated soium chlorideaqueous solution and dried over anhydrous magnesium sulfate. Then, thesolvent was distilled off under reduced pressure to obtain 2.8 g ofL-N-benzyloxycarbonyl-O-mesylprolinol as slightly yellow oily substance.

Rf: 0.36 (n-hexane/ethyl acetate=1/1)

(b) 555 mg of sodium hydride (60% in oil) was suspended in 15 ml of DMF,and 1.2 ml of thioacetic acid was dropwise added thereto at -15° C.under an argon atmosphere. The mixture was stirred at the sametemperature for ten minutes, and then a solution of 2.8 g of the mesylcompound obtained in step (a) in DMF (10 ml) was dropwise added theretoat -15° C. The mixture was stirred at room temperature overnight. Then,the reaction solution was poured into a saturated ammonium chlorideaqueous solution and extracted with ethyl acetate. The ethyl acetatelayer was washed with water and with a saturated sodium chloride aqueoussolution and dried over anhydrous magnesium sulfate. The solvent wasdistilled off under reduced pressure, and the residue thereby obtainedwas purified by silica gel column chromatography (n-hexane/ethylacetate=4/1) to obtain 1.06 g of the above identified compound asslightly yellow oily substance. Further, 1.53 g of the O-mesyl compoundwas recovered.

Rf: 0.49 (n-hexane/ethyl acetate=2/1)

(3)L-N-[(2RS)-3-[[(2S)-N-benzyloxycarbonyl-2-pyrrolidinyl]methyl]thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

211 mg of the thio ester obtbined in step (2) was dissolved in 2 ml ofmethanol, and a solution of 41 mg of sodium methoxide in methanol (1 ml)was dropwise added thereto at 0° C. under an argon atmosphere. Themixture was stirred at room temperature for 15 minutes. Then, 42 μl ofacetic acid was added to the reaction solution, and the mixture wasconcentrated under reduced pressure to dryness. To the residue, waterand ethyl acetate were added, and the organic layer was separated. Theorganic layer was washed with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. The solventwas distilled off under reduced pressure. The residue was dissolved in 2ml of DMF, and a solution of 250 mg ofL-N-[2-(1-naphthymethyl)acryloyl]norleucine tert-butyl ester in DMF (1ml) and 20 mg of potassium tert-butoxide were added thereto. The mixturewas stirred at room temperature for one hour and at 40° C. for one hour.Then, the reaction solution was washed with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure, and theresidue was purified by silica gel column chromatography (n-hexane/ethylacetate=5/1, and then 2/1) to obtain 218 mg of the above identifiedcompound from the second fraction. Further, 106 mg of the exo-methylenecompound was recovered from the first fraction.

Rf: 0.53 (n-hexane/ethyl acetate=1/1)

(4)(2S,3R,4S)-4-[L-N-(2S)-3-[[(2S)-N-benzyloxycarbonyl-2-pyrrolidinyl]methyl]sulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl]amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 200 mg of the sulfide compound obtained in step (3) was dissolved in10 ml of methanol, and 1 ml of a 30% hydrogen peroxide aqueous solutionand 20 mg of sodium tungstate dehydrate were added thereto. The mixturewas stirred at room temperature overnight. The reaction solution wasconcentrated under reduced pressure to dryness to obtain 209 mg of asulfone compound as colorless oily substance.

Rf: 0.26 (n-hexane/ethyl acetate=2/1)

(b) 209 mg of the sulfone compound obtained in step (a) was dissolved in2 ml of formic acid, and reacted at room temperature for one hour. Thereaction solution was concentrated under reduced pressure to dryness toobtain 191 mg of a carboxylic acid as colorless powder.

Rf: 0.26, 0.29 (benzene/methanol/acetic acid=10/1/0.25)

(c) 140 mg of the carboxylic acid obtained in step (b), 86 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride and 106 mg of BOP reagent were dissolved in 2 ml of DMF,and 100 μl of triethylamine was dropwise added thereto at -10° C. Themixture was stirred at room temperature for 5 hours and at 8° C.overnight. Then, ethyl acetate was added to the reaction solution, andthe mixture was washed sequentially with a 4% sodium hydrogencarbonateaqueous solution, with water and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. The solventwas distilled off under reduced pressure, and the residue was purifiedby silica gel column chromatography (chloroform/methanol=60/1) to obtain28 mg of the above identified compound from the first fraction ascolorless powder. Further, 75 mg of the optical isomer was obtained fromthe second fraction as colorless powder.

Rf: 0.33 (chloroform/methanol=20/1)

Mass spectrum m/z 877(M⁺ +1)

EXAMPLE 40(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1)L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionyl]norleucinetert-butyl ester

86.4 mg (2.2 eq) of 2-mercoptopyrimidine was dissolved in 1 ml of dryDMF, and 16.8 mg (2 eq) of sodium hydride (60% in oil) was addedthereto. The mixture was stirred at room temperature for 30 minutes, and193 mg of L-N-[(2R)-2-(1-naphthylmethyl)-3-(p-toluenesulfonyloxy)propionyl]norleucine tert-butyl ester dissolved in 1 ml of dry DMF wasadded thereto. The mixture was stirred at room temperature for fivehours. About 50 ml of water was added to the reaction solution and themixture was extracted with ethyl acetate. The organic layer was washedwith a saturated sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. The organic layer was subjected tofiltration, concentration and purification by silica gel columnchromatography (n-hexane/ethyl acete=3/1) to obtain 138.3 mg (yield:80%) of the above identified compound.

Rf: 0.29 (n-hexane/ethyl acetate=3/1)

NMR (300 MHz, CDOD): δppm: 0.88(3H,t), 1.28(4H,m), 1.39(9H,s),1.62(2H,m), 3.32(5H,m), 4.20(1H,dd), 7.03(1H,t), 7.38(2H,d), 7.48(2H,m),7.74(1H/t), 7.87(1H,d), 8.19(1H,d), 8.35(2H,d)

(2)L-N-[(2S)-2-(1-naphthylmethyl)-3-pyrimidin-2-yl)thiopropionyl]norleucine

70 mg of theL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionyl]norleucinetert-butyl ester obtained in step (1) was dissolved in 2 ml of drydichloromethane, and 0.5 ml of TFA was added thereto. The mixture wasstirred at room temperature for 4 hours. Further, 1 ml of TFA was addedthereto, and the mixture was stirred at room temperature for 2 hours.Benzene was added to the reaction solution, and the solvent wasdistilled off. The same operation was repeated three times. The residuewas dried under reduced pressure to obtain 61.5 mg (yield: 100%) of theabove identified compound.

Rf: 0.18 (benzene,/methanol/acetic acid=20/1/0.5)

NMR (300 MHz, CD₃ OD): δppm: 0.93(3H,t), 1.39(4H,m), 1.95(2H,m),3.20(2H,m), 3.55(1H,dd), 3.65(1H,dd), 3.97(1H,dd), 4.32(1H,dd),7.40(5H,m), 7.78(1H,d), 7.88(1H,m), 8.10(1H,m), 8.58(2H,d)

(3)(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

59.2 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionylinorleucinewas dissolved in 1 ml of dry DMF, and cooled with an ice bath. Then,58.2 mg (1.2 eq) of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride dissolved in 1 ml of dry DMF was added thereto, and 35μl (1.2 eq) of DPPA and 65 μl (3.4 eq) of triethylamine were addedthereto. The mixture was stirred at temperatures of 0° to 4° C. for 2.5days. Excess ethyl acetate was added to the reaction solution. Theorganic layer was washed with a sodium chloride aqueous solution anddried over anhydrous magnesium sulfate. Then, the organic layer waspurified by silica gel column chromatography (chloroform/methanol=50/1,and then 20/1) twice to obtain 20.8 mg (yield: 22%) of the aboveidentified compound.

Rf: 0.26 (chloroform/methanol=20/1)

Mass spectrum m/z 706(M⁺ +1)

IR (KBr): νcm⁻¹ : 1390, 1460, 1560, 1645, 2850, 2930, 3300, 3450

NMR (300 MHz, CDCl₂): δppm: 0.83(3H,t), 1.20(10H,m), 1.60(9H,m),2.49(2H,m), 2.62(1H,m), 2.78(3H,m), 3.08(1H,m), 3.44(7H,m), 2.70(4H,m),4.22(2H,m), 4.59(1H,br s), 5.91(2H,m), 6.98(1H,t), 7.47(4H,m),7.75(1H,m), 7.87(1H,m), 8.15(1H,m), 8.46(2H,d)

EXAMPLE 41(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1)L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucinetert-butyl ester

100 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionylinorleucinetert-butyl ester obtained in step (1) of Example 40, was dissolved in 1ml of acetic acid, and 600 μl of a 30% hydrogen peroxide aqueoussolution. The mixture was stirred at room temperature overnight. About20 ml of benzene was added to the reaction solution, and the solvent wasdistilled off under reduced pressure. The azeotropic operation withbenzene was repeated four times. The product was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=1/3, 1/5 and 0/100) toobtain 5.2 mg (yield: 50%) of the above identified compound.

Rf: 0.33 (n-hexane,/ethyl acetate=1/3)

NMR (300 MHz, CDCl₃): δppm: 0.88(3H,t), 1.28(4H,m), 1.40(9H,s),1.69(2H,m), 3.30(3H,m), 3.49(1H,dd), 4.12(1H,dd), 4.29(1H,dd),6.10(1H,d), 7.32(3H,m), 7.49(2H,m), 7.70(1H,d), 7.82(1H,d), 7.85(1H,d),8.62(2H,d)

(2)L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucine

130 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucinetert-butyl ester was dissolved in 2 ml of dry dichloromethane, and 1 mlof TFA was added thereto. The mixture was stirred at room temperaturefor 1.5 hours. Benzene was added to the reaction solution, and thesolvent was distilled off under reduced pressure. This operation wasrepeated four times. The product was dried under reduced pressure toobtain 113 mg (yield: 97%) of the above identified compound.

Rf: 0.09 (benzene/methanol/acetic acid=20/1/0.5)

NMR (300 MHz, CD₃ OD): δppm: 0.93(3H,t), 1.39(4H,m), 1.75(2H,m),3.20(1H,dd), 3.65(1H,dd), 3.97(1H,dd), 4.32(1H,dd), 7.40(5H,m),7.78(1H,d), 7.88(1H,m), 8.10(1H,m), 8.58(2H,d)

(3)(2S,3R,4S)-4-{L-N-[(2S)-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

110 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucinewas dissolved in 2 ml of dry DMF. The mixture was cooled with an icebath. Then, 101 mg (1.2 eq) of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride dissolved in 2 ml of dry DMF was added thereto, and 61μl (1.2 eq) of DPPA and 112 μl (3.4 eq) of triethylamine were addedthereto. The mixture was stirred at temperatures of 0° to 4° C. for 2.5days. The aftertreatment was conducted in the same manner as in step (2)of Example 40, and the product was purified by silica gel columnchromatography (chloroform/methanol=20/1) to obtain 64.3 mg (yield: 37%)of the above identified compound.

Rf: 0.2 (chloroform/methanol=20/1)

Mass spectrum m/z 738(M⁺ +1)

IR (KBr): νcm⁻¹ : 1120(SO₂), 1320(SO₂), 1390, 1460, 1540, 1560, 1655,2850, 2930, 3400

NMR (300 MHz, CDCl₃): δppm: 0.87(3H,t), 1.25(10H,m), 1.60(9H,m),2.48(2H,m), 2.62(1H,m), 2.75(3H,m), 3.29(2H,m), 3.46(3H,m), 3.65(5H,m),3.99(1H,m), 4.25(2H,m), 4.60(1H,br s), 6.02(1H,d), 6.27(1H,d),7.29(2H,m), 7.39(1H,t), 7.52(2H,m), 7.74(1H,d), 7.88(2H,m), 8.55(2H,d)

EXAMPLE 42(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1)L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucinetert-butyl ester

60 mg of theL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)thiopropionylinorleucinetert-butyl ester obtained in step (1) of Example 40 was dissolved in 0.4ml of acetic acid, and 27 μl (2 eq) of a 30% hydrogen peroxide aqueoussolution was added thereto. The mixture was stirred at room temperatureovernight. To the reaction solution, about 20 ml of benzene was added,and the solvent was distilled off. The azeotropic operation with benzenewas repeated 4 times. Then, the product was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=1/3, and 0/100) to obtain38.7 mg (yield: 63.3%) of the above identified compound.

Rf: 0.07 (n-hexane/ethyl acetate=1/3)

(2)L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucine

58 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucinetert-butyl ester was dissolved in 1 ml of dichloromethane, and 0.5 ml ofTFA was added thereto. The mixture was stirred at room temperature for1.5 hours. The aftertreatment was conducted in the same manner as instep (3) of Example 41 to obtain 52 mg (yield: 100%) of the aboveidentified compound.

Rf: 0.06 (benzene/methanol/acetic acid=20/1/0.5)

(3)(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

51.7 mg ofL-N-[(2S)-2-(1-naphthylmethyl)-3-(pyrimidin-2-yl)sulfinylpropionyl]norleucinewas dissolved in 1 ml of dry DMF, and the solution was cooled with anice bath. Then, 49 mg (1.2 eq) of(2R,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride dissolved in 1 ml of dry DMF was added to the solutionand 29 μl (1.2 eq) of DPPA and 55 μl (3.4 eq) of triethylamine werefurther added thereto. The mixture was stirred at 4° C. for 2.5 days.The aftertreatment was conducted in the same manner as in step (2) ofExample 40, and the product was purified by silica gel columnchromatography (chloroform/methanol=40/1) to obtain 31.5 mg of Isomer Aand 16.2 mg of Isomer B of the above identified compound, respectively.

Isomer A

Rf: 0.28 (chloroform/methanol 20/1)

Mass spectrum m/z 722(N⁺ +1)

IR (KBr): νcm¹⁻ : 1060(SO), 1390, 1460, 1560, 1650, 2860, 2930, 3300,3420

NMR (300 MHz, CDCl₃): δppm: 0.91(1H,t), 1.0-2.0(19H,m), 2.41(2H,m),2.58(1H,t), 2.82(4H,m), 3.27(3H,m), 3.45(5H,m), 3.64(3H,m), 4.22(1H,m),4.35(1H,m), 4.71(1H,br s), 6.37(1H,t), 6.60(1H,t), 7.09(1H,d),7.32(1H,t), 7.45(2H,m), 7.61(2H,m), 7.72(1H,m), 7.97(1H,m), 8.01(2H,d)

Isomer B

Rf: 0.23 (chloroform/methanol=20/1)

Mass spectrum m/z 721(M⁺ +1)

IR (KBr): νcm⁻¹ : 1060(SO), 1380, 1460, 1540, 1560, 1650, 2850, 2920,3300, 3420

NMR (300 MHz, CDCl₃): δppm: 0.83(3H,t), 1.20(2H,m), 1.65(8H,m),2.47(2H,m), 2.62(1H,m), 2.76(3H,m), 3.45(6H,m), 3.64(6H,m), 3.89(1H,m),4.32(1H,m), 4.68(1H,s), 6.07(1H,d), 6.14(1H,d), 7.39(3H,m), 7.57(2H,m),7.77(1H,d), 7.88(1H,d), 8.03(1H,d), 8.80(2H,d)

EXAMPLE 43(2S,3R,4S)-4-{L-N-[(2S)-2-(1-naphthylmethyl)-3-[[(2S)-2-pyrrolidinyl]methyl]sulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride

21.6 mg of the N-benzyloxycarbonyl compound obtained in step (4) ofExample 39 was dissolved in 2 ml of ethanol. The hydrogenation wasconducted at room temperature under an atmospheric pressure for 2 hoursby an addition of palladium black. The catalyst was removed byfiltration. 55 μl of 1N hydrochloric acid was added to the filtrate, andthe mixture was concentrated under reduced pressure to dryness. Theresidue was crystallized by an addition of diethyl ether to obtain 20.4mg of the above identified compound as colorless powder.

Rf: 0.63 (chloroform/methanol=5/1)

Mass spectrum m/z 743(M⁺ +1)

EXAMPLE 44(2S,3R,4S)-4-{L-N-[(2S)-2-benzyl-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-N-[(2RS)-2-ethoxycarbonyl-3-phenylpropionyl]norleucine tert-butylester

5 g of diethyl benzylmalonate was dissolved in 15 ml of ethanol, and anethanol solution (12 ml) of 1.15 g of potassium hydroxide was dropwiseadded thereto. The mixture was stirred at room temperature overnight.Then, the reaction solution was concentrated under reduced pressure todryness. The residue was dissolved in water and extracted with diethylether. The aqueous layer was adjusted to pH2 with 1N hydrochloric acidand extracted with diethyl ether. The diethyl ether layer was washedwith a saturated sodium chloride aqueous solution and then dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure to obtain 3.7 g of a half ester as colorless oily substance.

1 g of the half ester was dissolved in 10 ml of DMF, and a DMF solution(15 ml) of 1.45 g of DPPA was added thereto. A DMF solution (15 ml) of927 mg of L-norleucine tert-butyl ester containing 659 μl oftriethylamine was dropwise added thereto at -5° C. The mixture wasstirred at 5° C. for 2 hours and further at room temperature overnight.Then, ethyl acetate was added to the reaction solution, and the mixturewas washed sequentially with 0.5N hydrochloric acid, with a 4% sodiumhydrogencarbonate aqueous solution, with water and with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. Then, the solvent was distilled off under reduced pressure toobtain 1.99 g of the above identified compound as colorless powder.

Rf: 0.47 (n-hexane/ethyl acetate=3/1)

(2) L-N-[(2RS)-2-benzyl-3-hydroxypropionyl]norleucine tert-butyl ester

1.8 g of the L-N-acylnorleucine obtained in step (1) was dissolved in asolvent mixture of 20 ml of ethanol and 15 ml of THF, and 210 mg ofsodium borohydride and 240 mg of lithium chloride were added thereto.The mixture was stirred at room temperature for 2 hours. Then, 53 mg ofsodium borohydride and 60 mg of lithium chloride were further addedthereto. The mixture was stirred at room temperature for 2 hours. Then,396 μl of acetic acid was added thereto, and the mixture wasconcentrated under reduced pressure. To the residue, water and ethylacetate was added, and the ethyl acetate layer was separated. The ethylacetate layer was washed with a saturated sodium chloride aqueoussolution and dried over anhydrous magnesium sulfate. Then, the solventwas distilled off under reduced pressure to obtain 1.7 g of the aboveidentified compound as colorless powder.

Rf: 0.24, 0.31 (n-hexane/ethyl acetate=4/3)

(3) L-N-[(2S)-2-benzyl-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucinetert-butyl ester

(a) 400 mg of the alcohol compound obtained in step (2) was dissolved in6 ml of dichloromethane, and 116 μl of methanesulfonyl chloride and 224μl of triethylamine were dropwise added thereto at -5° C. The mixturewas stirred at room temperature for one hour. Then, the reactionsolution was diluted with ethyl acetate. The mixture was washed withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous magnesium sulfate. Then, the solvent was distilled offunder reduced pressure to obtain 538 mg ofL-N-[(2RS)-2-benzyl-3-mesyloxypropionylnorleucine tert-butyl ester ascolorless solid.

Rf: 0.37 (n-hexane/ethyl acetate=2/1)

(b) 55 mg of sodium hydride (60% in oil) was suspended in 3 ml of DMF,and a DMF suspension (3 ml) of 154 mg of 2-mercaptopyrimidine was addedthereto at -5° C. under an argon atmosphere. The mixture was stirred atroom temperature for 20 minutes. Then, a DMF solution (4 ml) of 500 mgof O-mesyl compound obtained in step (a) was dropwise added thereto at-5° C. The mixture was stirred at room temperature for three hours, andthen the reaction solution was poured into a saturated ammonium chlorideaqueous solution and extracted with ethyl acetate. The ethyl acetatelayer was washed with a saturated sodium chloride aqueous solution anddried over anhydrous magnesium sulfate. The solvent was distilled offunder reduced pressure, and the residue was purified by silica gelcolumn chromatography (n-hexane./ethyl acetate=5/1) to obtain 100 mg ofL-N-[(2S)-2-benzyl-3-(pyrimidin-2-yl)thiopropionyl]norleucine tert-butylester as colorless powder from the first fraction.

Rf: 0.50 (n-hexane/ethyl acetate=4/3)

(c) 95 mg of the sulfide compound obtained in step (b) was dissolved in4 ml of methanol, and 0.4 ml of a 30% hydrogen peroxide aqueous solutionand 10 mg of sodium tungstate dehydrate were added thereto. The mixturewas stirred at room temperature overnight. To the reaction solution,water was added, and methanol was distilled off under reduced pressure.To the residue, water and ethyl acetate were added, and the organiclayer was separated. The organic layer was washed with a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. Then, the solvent was distilled off under reduced pressure, andthe residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=4/3) to obtain 69 mg of the above identifiedcompound as colorless powder.

Rf: 0.19 (n-hexane/ethyl acetate=1/1)

(4)(2S,3R,4S)-4-{L-N-[(2S)-2-benzyl-3-(pyrimidin-2-yl)sulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 63.6 mg of the sulfone compound obtained in step (3) was dissolvedin I ml of dichloromethane, and 0.5 ml of TFA was added thereto. Themixture was stirred at room temperature for 30 minutes. Further, 0.5 mlof TFA was added thereto, and the mixture was stirred at roomtemperature for 30 minutes. Then, the reaction solution was concentratedunder reduced pressure to dryness. Azeotropic evaporation with benzenewas repeated twice to obtain 54.9 mg of a carboxylic acid as slightlyyellow solid.

Rf: 0.10 (benzene/methanol/acetic acid=20/1/0.5)

(b) 54.9 mg of the carboxylic acid obtained in step (a), 48 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride and 60 mg of BOP reagent were dissolved in 2 ml of DMF,and 56 μl of triethylamine was added thereto at -5° C. The mixture wasstirred at -5° C. for 30 minutes and further at 8° C. overnight. Then,to the reaction solution, ethyl acetate was added. The mixture waswashed with a 4% sodium hydrogencarbonate aqueous solution and with asaturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel column chromatography(chloroform/methanol=60/1) to obtain 60.5 mg of the above identifiedcompound as colorless powder.

Rf: 0.21 (chloroform/methanol=20/1)

Mass spectrum m/z 688(M⁺ +1)

EXAMPLE 45(2S,3R,4S)-4-{L-O-acetyl-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]homoseryl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) L-O-acetyl-N-tert-butoxycarbonylhomoserine benzyl ester

(a) 117 mg of L-homoserine was dissolved in 3 ml of ethanol/water (2/1),and 0.99 ml of a 1N sodium hydroxide aqueous solution was added thereto.Then, 1 ml of a THF solution of 240 mg of di-tert-butyl dicarbonate wasadded thereto. The mixture was stirred at room temperature overnight.The unreacted reagent was extracted from the reaction solution withdiethyl ether, and the residual aqueous layer was adjusted to pH2 by anaddition of 1N hydrochloric acid under cooling with ice. The aqueouslayer was extracted with ethyl acetate, and the ethyl acetate layer wasdried over anhydrous magnersium sulfate. Then, the solvent was distilledoff under redcued pressure to obtain 210 mg ofL-N-tert-butoxycarbonylhomoserine as colorless oily substance.

Rf: 0.22 (chloroform/methanol/acetic acid=10/1/0.2)

(b) 210 mg of L-N-tert-butoxycarbonylhomoserine was dissolved in 3 ml ofethanol, and 0.96 ml of a 1N sodium hydroxide aqueous solution was addedthereto. The mixture was stirred at room temperature for one day. Thesolvent of the reaction solution was distilled off under reducedpressure, and the residue was dissolved in 3 ml of DMF. 132 μl of benzylbromide was added to the solution, and the mixture was stirred at roomtemperature overnight. The reaction solution was diluted with 30 ml ofethyl acetate. The mixture was washed sequentially with a saturatedsodium hydrogencarbonate aqueous solution, with water and with asaturated sodium chloride aqueous solution and dried over magnesiumsulfate. The solvent was distilled off under reduced pressure, and theresidue was purified by silica gel column chromatography (n-hexane/ethylacetate=1/1) to obtain 266 mg of L-N-tert-butoxycarbonylhomoserinebenzyl ester as colorless oily substance.

Rf: 0.55 (n-hexane/ethyl acetate=1/2)

(c) 266 mg of L-N-tert-butoxycarbonylhomoserine benzyl ester wasdissolved in 3 ml of pyridine, and 2 ml of acetic anhydride was addedthereto. The mixture was stirred at room temperature for 18 hours. Thereaction solution was poured into ice water and extracted with ethylacetate. The mixture was washed sequentially with a 1N hydrochloricacid, with a saturated sodium hydrogencarbonate aqueous solution andwith a saturated sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. Then, the solvent was distilled off underreduced pressure, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=3/1) to obtain 273 mg ofL-O-acetyl-N-tert-butoxycarbonylhomoserine benzyl ester as colorlessoily substance.

Rf: 0.34 (n-hexane/ethyl acetate=2/1)

(2) L-O-acetylhomoserine benzyl ester hydrochloride

215 mg of L-O-acetyl-N-tert-butoxycarbonylhomoserine benzyl ester wasdissolved in 2 ml of dioxane, and 3.4 ml of a 3.6M hydrogenchloride/dioxane solution was added thereto under cooling with ice. Themixture was stirred at room temperature for 2.5 hours. The reactionsolution was subjected to distillation under reduced pressure forremoval of the solvent to obtain 174 mg of L-O-acetylhomoserine benzylester hydrochloride as colorless oily substance.

Rf: 0.75 (chloroform/methanol/aqueous ammonia=10/1/0.5)

(3)L-O-acetyl-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}homoserin

(a) 128 mg of (2RS)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionic acidwas dissolved in 0.3 ml of DMF, and 78 mg of 1-hydroxybenzotriazole and103 mg of DCC were sequentially added thereto under cooling with ice. Asolution of 174 mg of L-O-acetylhomoserine benzyl ester hydrochloridedissolved in 0.5 ml of DMF and neutralized with 86 μl of triethylamine,was added thereto. The temperature was returned to room temperature, andthe mixture was stirred overnight. The insolubles were removed from thereaction solution by filtration. The filtrate was diluted with ethylacetate, washed with 1N hydrochloric acid, with a saturated sodiumhydrogencarbonate aqueous solution and with a saturated sodium chlorideaqueous solution and dried over anhydrous magnesium sulfate. Then, thesolvent was distilled off under reduced pressure, and the residue waspurified by silica gel column chromatography (n-hexane/ethylacetate=1/1) to obtain 55.6 mg ofL-O-acetyl-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}homoserinebenzyl ester as colorless crystals.

Rf: 0.50 (n-hexane/ethyl acetate=1/2)

(b) 55.6 mg ofL-O-acetyl-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}homoserinebenzyl ester was dissolved in 3 ml of ethanol and hydrogenated atordinary temperature under an atmospheric pressure by an addition ofpalladium black. The catalyst was removed by filtration, and then thesolvent was distilled off under reduced pressure to obtain 46.3 mg ofL-O-acetyl-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}homoserineas colorless oily substance.

Rf: 0.51 (chloroform/methanol/acetic acid=10/1/0.5)

(3)(2S,3R,4S)-4-{L-O-acetyl-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]homoseryl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

47.1 mg ofL-O-acetyl-N-{(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl}homoserinewas dissolved in 0.2 ml of dry DMF, and 19 μl of triethylamine, 29 μl ofDPPA and 0.5 ml of a DMF solution of 51.5 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride neutralized with 40 μl of triethylamine, was addedthereto. The mixture was stirred at room temperature overnight. To thereaction solution, 30 ml of ethyl acetate was added, and washed withwater and with a saturated sodium chloride aqueous solution and driedover anhydrous magnesium sulfate. The solvent was distilled off underreduced pressure, and the residue was purified by silica gel columnchromatography (chloroform/methanol=30/1) to obtain 43.0 mg of the aboveidentified compound as colorless amorphous.

Rf: 0.4.0 (chloroform/methanol=10/1)

Mass spectrum m/z 718(M⁺ +1) NMR (300 MHz, CDCl₃): δppm:0.80-1.04(3H,m), 1.20(3H,t,J=7.6 Hz), 1.10-2.15(15H,m), 1.97(3H,s),2.41-3.00(9H,m), 3.03(1H,dd,J=2,14 Hz), 3.25-3.78(10H,m),3.96-4.48(4H,m), 4.52(1H,br s), 6.38(1H,d,J=9 Hz), 6.50(1H,d,J=6 Hz),7.30-7.62(4H,m), 7.79(1H,d,J=8 Hz), 7.89(1H,d,J=8 Hz), 7.99(1H,d,J=8 Hz)

EXAMPLE 46(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]homoseryl}amino-5-cyclohexyl-2,3-pentanediol

35.0 mg of the compound obtained in Example 45 was dissolved in 1 ml ofmethanol, and 180 μl of aqueous ammonia was added thereto. The mixturewas stirred at room temperature overnight. The reaction solution wassubjected to distillation under reduced pressure for removal of thesolvent, and the residue was purified by silica gel columnchromatography (chloroform/methanol=10/1) to obtain 19.8 mg of the aboveidentified compound as colorless crystals.

Rf: 0.37 (chloroform/methanol=10/1)

Mass spectrum m/z 676(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.86-1.04(2H,m), 1.14-2.06(16H,m),2.46-2.60(2H,m), 2.64-2.94(5H,m), 3.01(1H,dd,J=1.8,13.5 Hz),3.29-3.51(5H,m), 3.59-3.78(7H,m), 4.22(1H,dt,J=6.0,9.3 Hz),4.41-4.47(1H,m), 4.49(1H,br s), 6.22(1H,d,J=9.0 Hz), 6.81(1H,d,J=6.3Hz), 7.32-7.62(4H,m), 7.79(1H,d,J=8.4 Hz), 7.89(1H,d,J=8.4 Hz),7.98(1H,d,J=8.4 Hz)

EXAMPLE 47(2S,3R,4S)-4-{L-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) (2R)-3-hydroxy-2-(1-naphthylmethyl)proplonic acid

(2R)-3-benzyloxy-2-(1-naphthylmethyl)propionic acid was dissolved in 6ml of THF, and 3 ml of cyclohexene, 2.5 ml of 1N hydrochloric acid and400 mg of 10% palladium carbon were added thereto. The mixture wasrefluxed under heating for 48 hours. After filtration, the solvent wasdistilled off under reduced pressure, and the residue was divided withethyl acetate and a 4% sodium hydrogencarbonate aqueous solution. Theaqueous layer was adjusted to pH2 with 1N hydrochloric acid undercooling with ice and extracted with ethyl acetate. The ethyl acetatelayer was washed sequentially with water and a saturated sodium chlorideaqueous solution and dried over anhydride sodium sulfate to obtain 212mg of (2R)-3-hydroxy-2-(1-naphthylmethyl)propionic acid as colorlessoily substance.

Rf: 0.40 (n-hexane/ethyl acetate/acetic acid=6/6/0.2)

(2) L-N-[(2R)-3-hydroxy-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

79 mg of (2R)-3-hydroxy-2-(1-naphthylmethyl)propionic acid was dissolvedin 0.5 ml of DMF, and 1.0 ml of a DMF solution of 84 mg of L-norleucinetert-butyl ester, 82 mg of 1-hydroxybenzotriazole monohydrate and 79 mgof DCC were added thereto under stirring at -15° C. The mixture wasstirred at -15° C. for 1 hour and then at room temperature overnight.Then, the reaction solution was treated in the same manner as in Example1 (3), and the product was purified by silica gel column chromatography(n-hexane/ethyl acetate=2/1) to obtain 79 mg ofL-N-[(2R)-3-hydroxy-2-(1-naphthylmethyl)propionyl]norleucine tert-butylester as white solid.

Rf: 0.26 (n-hexane/ethyl acetate=2/1)

(3) L-N-[(2S)-3-furfurylthio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester

(a) 78 mg ofL-N-[(2R)-3-hydroxy-2-(1-naphthylmethyl)propionyl]norleucine tert-butylester was dissolved in 0.8 ml of dry pyridine, 80 mg ofp-toluenesulfonyl chloride was added thereto. The mixture was stirred atroom temperature overnight. The reaction solution was poured into icewater and extracted with ethyl acetate. The extract was washedsequentially with 1N hydrochloric acid, water, a saturated sodiumhydrogencarbonate aqueous solution and a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. Then, thesolvent was distilled off under reduced pressure, and the residue waspurified by silica gel column chromatography (n-hexane/ethylacetate=3/1) to obtain 86 mg ofL-N-[(2R)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl]norleucinetert-butyl ester as colorless oily substance.

Rf: 0.54 (n-hexane/ethyl acetate=2/1)

(b) 11 mg of sodium hydride (60% in oil) was suspended in 0.3 ml of dryDMF, and 30 μl of furfurylmercaptan was added thereto at 0° C. understirring. The mixture was stirred at room temperature for 30 minutes.Then, 0.7 ml of a dry DMF solution of 86 mg ofL-N-[(2R)-2-(1-naphthylmethyl)-3-p-toluenesulfonyloxypropionyl]norleucinetert-butyl ester was added thereto at 0° C., and the mixture was stirredat room temperature for one hour. To the reaction solution, ethylacetate was added, and the mixture was washed sequentially with waterand a saturated sodium chloride aqueous solution. The organic layer wasdried over anhydrous sodium sulfate, and the solvent was distilled offunder reduced pressure. Then, the residue was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate 10/1) to obtain 64 mg ofthe above identified compound as colorless oily substance.

Rf: 0.28 (n-hexane/ethyl acetate=5/1)

(4)L-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucine

(a) 60 mg ofL-N-[(2S)-3-furfurylthio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 1.0 ml of methanol, and 0.21 ml of a30% hydrogen peroxide aqueous solution and 6 mg of sodium tungstatedehydrate were added thereto. The mixture was stirred at roomtemperature for 4 hours. To the reaction solution, ethyl acetate wasadded, and the mixture was washed sequentially with water and asaturated sodium chloride aqueous solution. The organic layer was driedover anhydrous sodium sulfate. Then, the solvent was distilled off underreduced pressure to obtain 57 mg ofL-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester as colorless oily substance.

Rf: 0.38 (n-hexane/ethyl acetate=2/1)

(b) 55 mg ofL-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 0.3 ml of dichloromethane, and 0.3 mlof TFA was added thereto. The mixture was stirred at room temperaturefor one hour. To the reaction solution, ethyl acetate was added. Themixture was washed sequentially with water and a saturated sodiumchloride aqueous solution and dried over anhydrous sodium sulfate. Thesolvent was distilled off under reduced pressure to obtain 52 mg of theabove identified compound as colorless oily substance.

Rf: 0.27 (n-hexane/ethyl acetate/acetic acid=6/6/0.2)

(5)(2S,3R,4S)-4-{L-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

50 mg ofL-N-[(2S)-3-furfurylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucinewas dissolved in 0.4 ml of dry DMF, and 18 μl of triethylamine, 28 μl ofDPPA and 0.6 ml of a dry DMF solution of 53.5 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was added thereto and 41 μl of triethylamine was furtheradded thereto. The mixture was stirred at room temperature overnight.Then, the same procedure as in Example 16 (5)-(b) was conducted, and thepurification by silica gel column chromatography(chloroform/methanol=100/1, and then 50/1) was conducted to obtain 64 mgof the above identified compound as white powder.

Rf: 0.29 (chloroform/methanol=20/1)

Mass spectrum (FAB) m/z 740(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.79-0.82(3H,m), 1.05-1.38(6H,m),1.38-1.80(9H,m), 2.40-2.55(2H,m), 2.55-2.82(4H,m), 3.05(1H,dd,J=14.2,3.2Hz), 3.15-3.32(1H,m), 3.32-3.75(9H,m), 4.13-4.32(4H,m), 5.88(1H,d,J=7.9Hz), 6.02(1H,d,J=8.7 Hz), 6.34(1H,d,J=0.8 Hz), 6.38(1H,d,J=0.8 Hz),7.28-7.65(4H,m), 7.79(1H,d,J=7.9 Hz), 7.90(1H,d,J=7.9 Hz),7.99(1H,d,J=7.9 Hz)

EXAMPLE 48 (2S,3R,4S)-4-{L-N-[(2S orR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 114 mg of the isomer having a high Rf value of L-N-[(2S orR)-3-(2-hydroxyethyl)thio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 1.06 ml of acetic acid, and 28.1 μl ofa 30% hydrogen peroxide aqueous solution was added thereto. The mixturewas stirred at room temperature for 30 minutes, and then the solvent wasdistilled off under reduced pressure. To the residue, benzene was added,and benzene was distilled off under reduced pressure. This operation wasrepeated. The syrup thereby obtained was purified by silica gel columnchromatography (chloroform/methanol=30/1) to obtain 117 mg of L-N-[(2SorR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester as colorless oily substance.

Rf: 0.30 (chloroform/methanol=20/1)

NMR (300 MHz, CDCl₃): δppm: 0.84(3H,q,J=7.6 Hz) 1.10-1.47(13H),1.47-1.85(2H), 2.63-3.08(3H), 3.20-3.62(4H), 4.00-4.38(3H),5.98(0.3H,d,J=7.9 Hz), 6.34(0.7H,d,J=7.9 Hz), 7.28-7.42(2H), 7.50(2H,m),7.73(1H,d,J=7.9 Hz), 7.85(1H,d,J=7.9 Hz), 8.00(0.7H,d,J=7.9 Hz),8.06(0.3H,d,J=7.9 Hz)

(b) 109 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 0.4 ml of dry dichloromethane, and 0.4ml of TFA was added thereto. The mixture was stirred at room temperaturefor 2.5 hours. Then, the solvent was distilled off. To the residue,benzene was added, and the mixture was concentrated under reducedpressure. This operation was repeated to obtain 94.8 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucineas colorless solid.

Rf: 0.30, 0.23 (chloroform/methanol/acetic acid=10/0.5/0.1)

NMR (300 MHz, CD₃ OD): δppm: 0.90(3H), 1.20-1.42(4H), 1.55-1.85(2H),2.72-3.02(3H), 3.02-3.62(4H), 3.80-3.96(2H), 4.24(0.3H,m), 4.35(0.7H,m),7.37(2H,m), 7.52(2H,m), 7.75(1H,m), 7.85(1H,d,J=8.1 Hz), 8.18(1H,d,J=8.1Hz)

(c) 54.6 mg of L-N-[(2S orR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucinewas dissolved in 0.2 ml of dry DMF, and 32.3 mg of1-hydroxybenzotriazole and 41.2 mg of DCC were added thereto at 0° C.under stirring. Then, 60.4 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was dissolved in 0.2 ml of dry DMF, and 34.0 mg oftriethylamine was added thereto for neutralization. This solution wasadded to the previous solution, and the mixture was stirred at 0° C. for2 hours and at 5° C. overnight. The precipitated dicyclohexyl urea wasremoved by filtration, and solvent of the filtrate was distilled off. Tothe residue, a small amount of chloroform was added, and the insolubleswere removed by filtration. Then, the solvent of the filtrate wasdistilled off under reduced pressure. This operation was repeated twice.The residue thereby obtained was dissolved in 10 ml of ethyl acetate.The ethyl acetae layer was washed sequentially with a 4% sodiumhydrogencarbonate aqueous solution, with water and with a saturatedsodium aqueous solution and dried over anhydride sodium sulfate. Thesolvent was distilled off under reduced pressure, and the residue waspurified by silica gel column chromatography (chlorofrom/methanol=15/1)to obtain 32.0 mg of the isomer having a high Rf value (Example 48-A)and 23.4 mg of the isomer having a low Rf value (Example 48-B) of(2S,3R,4S)-4-{L-N-1(2S orR)-3-(2-hydroxyethyl)sulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solids, respectively.

Isomer having a high Rf value (Example 48-A):

Rf: 0.33 (chloroform/methanol=10/1)

Mass spectrum m/z 688(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.80-1.08(4H), 1.10-1.85(18H), 2.48(2H),2.57-2.86(6H), 3.08(2H,m), 3.30-3.54(5H), 3.54-3.75(5H), 3.98(2H,m),4.25(2H,m), 4.70(1H,br), 6.46(1H,d,J=8.4 Hz), 6.77(1H,br),7.32-7.46(2H), 7.55(2H,m), 7.79(1H,d,J=7.8 Hz), 7.89(1H,dd,J=2.1,7.5Hz), 7.99(1H,d,J=8.1 Hz)

Isomer having a low Rf value (Example 48-B):

Rf: 0.29 (chloroform/methanol=10/)

Mass spectrum m/z 688(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.70-1.05(4H), 1.05-1.38(8H),1.38-1.90(10H), 2.48(2H,Br), 2.57-3.00(7H), 3.21-3.56(6H), 3.66(4H),3.94-4.30(4H), 4.68(1H,br), 6.30(2H), 7.30-7.45(2H), 7.55(2H,m),7.78(1H), 7.88(1H), 7.95-8.09(1H)

EXAMPLE 49(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholiono-2,3-pentanediol

(a) 133.3 mg ofL-N-[(2S)-3-ethylthio-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 1 ml of acetic acid, and 31.9 μl of a30% hydrogen peroxide aqueous solution was added thereto. The mixturewas stirred at room temperature for 25 minutes. Then, the solvent wasdistilled off under reduced pressure. To the residue., benzene wasadded, and benzene was distilled off under reduced pressure. Thisoperation was repeated to obtain 136.1 mg ofL-N-[(2S)-3-ethylsulfinyl-3--(1-naphthylmethyl)propionyl]norleucinetert-butyl ester as colorless oily substance.

Rf: 0.33 (chloroform/ethyl acetate=1/1)

Mass spectrum m/z 460(M⁺ +1)

(b) 129.2 mg ofL-N-1(2S)-3-ethylsulfinyl-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 0.5 ml of dry dichloromethane, and 0.5ml of TFA was added thereto. The mixture was stirred at room temperaturefor 2.5 hours. Then, the solvent was distilled off. The residue wasdissolved in benzene, and the mixture was concentrated under reducedpressure. This operation was repeated to obtain oily substance. The oilysubstance was solidified with chloroform/diethyl ether. The solvent wasdistilled off under reduced pressure to obtain 117 mg ofL-N-[(2S)-3-ethylsulfinyl-2-(1-naphthylmethyl)propionyl]norleucine ascolorless solid.

Rf: 0.37, 0.41 (chloroform/methanol/acetic acid=10/0.5/0.1)

NMR (300 MHz, CDCl₃): δppm: 0.83(3H), 1.05-1.39(7H), 1.70(1H,m),1.92(1H,m), 2.62-2.82(2H), 2.90(0.3H,dd,J=9.9,13.5 Hz), 3.08-3.58(3.7H),3.70(1H,m), 4.,I)2(0.3H,dt,J=5.4,5.4 Hz), 4.40(0.7H,dt,J=5.8,5.8 Hz),7.28-7.67(6H), 7.92(0.7H), 8.08(0.3H,d,J=8.1 Hz)

(c) 60 mg ofL-N-[(2S)-3-ethylsulfinyl-2-(1-naphthylmethyl)propionyl]norleucine wasdissolved in 0.2 ml of dry DMF, and 36.4 mg of 1-hydroxybenzotriazoleand 42.9 mg of DCC were added thereto at 0° C. under stirring. Then,69.5 mg of (2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride was dissolved in 0.2 ml of dry DMF, 39.1 mg oftriethylamine was added thereto for neutralization. This solution wasadded to the previous reaction solution, and the mixture was stirred at0° C. for two hours and at 5° C. overnight. The precipitateddicyclohexylurea was removed by filtration and washed with a smallamount of chloroform. This washing solution and the filtrate were puttogether, and concentrated under reduced pressure. The concentratedsolution was diluted with 20 ml of ethyl acetate. The organic layer waswashed sequentially with a 4% sodium hydrogencarbonate aqueous solution,with water and with a saturated sodium chloride aqueous solution anddried over anhydrous sodium sulfate. The solvent was distilled off underreduced pressure, the residue was purified by silica gel columnchromatography (chloroform/methanol=60/1) to obtain 38.3 mg of theisomer having a high Rf value (Example 49-A) and 16.1 mg of the isomerhaving a low Rf value (Example 49-B) of(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfinyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolas colorless solids, respectively.

Isomer having a high Rf value (Example 49-A):

Rf: 0.5 (chloroform/methanol=10/1)

Mass spectrum m/z 672(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.75-1.86(25H), 2.27(1H,m), 2.40-2.69(4H),2.78(4H), 3.04(1H,dd,J=9.2,13.1 Hz), 3.32(2H), 3.42-3.62(7H), 4.25(2H),4.68(1H,br), 6.34(1H,d,J=9.3 Hz), 6.90(1H,d,J=5.4 Hz), 7.32-7.48(2H),7.78(1H,d,J=7.8 Hz), 7.89(1H,dd,J=1.4,7.8 Hz) 7.98(1H,d,J=8.7 Hz)

Isomer having a low Rf value (Example 49-B):

Rf: 0.43 (chloroform/methanol=10/1)

Mass spectrum m/z 672(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.77-2.00(25H), 2.49(2H), 2.55-2.85(7H),3.04(1H,m), 3.32(1H,m), 3.46(4H), 3.64(4H), 4.15(1H,m), 4.25(1H,m),6.19(1H), 6.46(1H), 7.32-7.47(2H), 7.47-7.63(2H), 7.78(1H,d,J=7.8 Hz),7.89(1H,d,J=8.1 Hz), 8.08(1H,d,J=8.1 Hz)

EXAMPLE 50N-[(2S,3R,4S)-4-[L-N-[(2R)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl]amino-5-cyclohexyl-2,3-dihydroxypentylmorpholineN-oxide

25 mg of(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolwas dissolved in 1.5 ml of methanol, and 150 μl of a 30% hydrogenperoxide aqueous solution was added thereto. 2 mg of sodium tungstatedihydrate was added thereto as a catalyst, and the mixture was stirring.The mixture was stirred at room temperature for three hours, and theinsolubles were removed by filtration. The filtrate was diluted with 15ml of ethyl acetate and washed with a 4% sodium carbonate aqueoussolution (10 ml×1 time) and then with a saturated sodium aqueoussolution (10 ml×2 times). The ethyl acetate layer was dried overanhydrous sodium sulfate and then concentrated under reduced pressure toobtain 25 mg of the above identified compound as white solid.

Mass spectrum m/z 704(M⁺ +1)

EXAMPLE 51 (2S,3R,4S)-4-{L-N-[(2S orR)-3-cyclopentanesulfonyl-2-benzylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 210 mg of (2S or R)-3-cyclopentanesulfonyl-2-benzylpropionic acidwas dissolved in 3 ml of dry DMF, and 0.8 ml of a dry DMF solution of0.15 ml of triethylamine, 0.18 ml of DPPA and 0.15 g of norleucinetert-butyl ester was added thereto at -15° C. by a usual DPPA method.The mixutre was subjected to usual aftertreatment, and the product waspurified by silica gel column chromatography to obtain 122 mg ofL-N-((2S or R)-3-cyclopentanesulfonyl-2-benzylpropionyl)norleucinetert-butyl ester as white solid.

NMR (300 MHz, CDCl₃): δppm: 2.81-3.18(4H,m), 3.25(0.75H,m),3.40(0.25H,m), 3.59(1H,m), 4.23(0.25H,m), 4.45(0.75H,m),5.91(0.25H,d,J=8 Hz), 6.09(0.75H,d,J=8 Hz), 7.1-7.3(5H,m)

(b) L-N-((2S or R)-3-cyclopentanesulfonyl-2-benzylpropionyl)norleucinetert-butyl ester obtained in step (a) was subjected to deesterificationwith 4.2 ml of dichloromethane/TFA (1/1). 108 mg ofL-N-(3-cyclopentanesulfonyl-2-benzylpropionyl)norleucine therebyobtained was condensed with(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanediol in 3 ml ofdry DMF by using a DPPA method. The product was subjected to usual workup and purified by silica gel column chromatography to obtain 62 mg ofthe above identified compound, 13 mg of (2S,3R,4S)-4-{L-N-[(2R orS)-3-cyclopentanesulfonyl-2-benzylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanedioland 80 mg of a mixture of the both isomers as white solids,respectively.

S or R isomer:

NMR (300 MHz, CDCl₃): δppm: 2.49(2H,m), 2.62(1H,m), 2.70-3.05(6H,m),3.15(1H,m), 3.26(1H,m), 3.6-3.7(3H,m), 3.68(4H,m), 4.18-4.31(2H,m),4.60(1H,br s), 6.00(1H,d,J=9.5 Hz), 6.08(1H,d,J=7 Hz), 7.2-7.4(5H,m)

R or S isomer:

NMR (300 MHz, CDCl₃): δppm: 2.50(2H,m), 2.63(1H,m), 2.7-2.8(2H,m),2.83-3.06(4H,m), 3.16(1H,m), 3.37-3.82(8H,m), 4.04(1H,m), 4.91(1H,br),5.81(1H,d,J=8 Hz), 7.08(1H,d,J=9 Hz), 7.14-7.35(5H,m)

EXAMPLE 52N-[(2S,3R,4S)-4-[L-N-[(2S)-3-cyclopentanesulfonyl-2-benzylpropionyl]norleucyl]amino-5-cyclohexyl-2,3-dihydroxypentyl]morpholineN-oxide

25 mg of(2S,3R,4S)-4-{L-N-[(2S)-3-cyclopentanesulfonyl-2-benzylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolobtained in Example 51 was dissolved in 1.5 ml of methanol, and 150 μlof a 30% hydrogen peroxide aqueous solution was added thereto. 2 mg ofsodium tungstate dehydrate was added thereto as a catalyst, and themixture was stirred. The mixture was stirred at room temperature for 3hours, and then the insolubles were removed by filtration. The filtratewas dilute with 15 ml of ethyl acetate and washed with a 4% sodiumcarbonate aqueous solution (10 ml×1 time) and then with a saturatedsodium chloride aqueous solution (10 ml×2 times). The ethyl acetatelayer was dried over anhydride sodium sulfate, and then concentratedunder reduced pressure to obtain 25 mg of the above identified compoundas white solid.

Mass spectrum m/z 694(M⁺ +1)

EXAMPLE 53 (2R)-3-benzyloxy-2-(1-naphthylmethyl)propionic acid

(1) (E)-4-benzyloxy-2-buten-1-ol

(a) 14.6 g of sodium hydride (60% in oil) was washed with n-pentaneunder argon, and dried. 150 ml of dry DMF was added thereto forsuspension, and 75 g of (Z)-2-buten-1,4-diol was dropwise added theretoover a period of 30 minutes under stirring at 0° C. The mixture wasstirred at room temperature for 1.5 hours, and then 44 g of benzylbromide was added thereto under stirring at 0° C. The mixture wasstirred at the same time for 30 minutes and then the temperature wasreturned to room temperature and stirred at 50° C. overnight. Thereaction solution was poured into ice water, extracted with ether, andthe ether solution was washed sequentially with water and a saturatedsodium chloride aqueous solution and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure, and theresidue was subjected to distillation under reduced pressure (2.5 mmHg,134°-138° C.) to obtain 29 g of (Z)-4-benzyloxy-2-buten-1-ol ascolorless oily substance.

Rf: 0.49 (n-hexane/ethyl acetate=1/1)

(b) 11.1 g of pyridinium chlorochromate and 12 g of celite weresuspended in 100 ml of dry dichloromethane, and 6 g of(Z)-4-benzyloxy-2-buten-1-ol was added thereto under stirring at 0° C.The mixture was stirred at room temperature for three hours, and thendiethyl ether was added thereto. The insolubles were removed byfiltration. The filtrate was subjected to distillation under reducedpressure for removal of the solvent, and the residue was purified bysilica gel column chromatography (diethyl ether) to obtain 3.9 g of(Z)-4-benzyloxy-butenal as slightly yellow oily substance.

Rf: 0.59 (n-hexane/ethyl acetate=1/1)

(c) 3.9 g of (Z)-4-benzyloxy-2-butenal was dissolved in 60 ml ofethanol, and 850 mg of sodium borohydride was added thereto understirring at 0° C. The mixture was stirred at 0° C. for 1.5 hours. Thereaction solution was poured into ice water and extracted with ethylacetate. The ethyl acetate solution was washed sequentially with waterand with a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. Then, the solvent was distilled off underreduced pressure, and the residue was subjected to distillation underreduced pressure (2.0 mmHg, 142° C.) to obtain 2.2 g of(E)-4-benzyloxy-2-buten-1-ol as colorless oily substance.

Rf: 0.49 (n-hexane/ethyl acetate=1/1)

(2)(2R,3R)-4-benzyloxy-1-tert-butyldimethylsilyloxy-3-(1-naphthylmethyl)-2-butanol

(a) In 190 ml of dry dichloromethane, 3.3 g of a molecular sieves(powder, 3A) was suspended, and 4.2 ml of isopropyl orthotitanate and2.9 ml of diethyl L(+)-tartarate were added thereto under stirring at-23° C. The mixture was stirred at the same temperature for 15 minutes.then, 3 ml of a dry dichloromethane solution of 4.7 g of(E)-4-benzyloxy-2-buten-1-ol was added thereto, and the mixture wasstirred at the same temperature for 5 minutes. 11 ml oftert-butylhydroxyperoxide (5.17M dichloromethane solution) was addedthereto, and the mixture was stirred for further seven hours. Then, thereaction solution was left to stand at -23° C. overnight. To thereaction solution, 190 ml of diethyl ether and 4.2 ml of a saturatedsodium sulfate aqueous solution were added, and the mixture was stirredat room temperature for 4 hours. The insolubles were removed byfiltration, and the solvent was distilled off under reduced pressure.The residue was dissolved in 240 ml of diethyl ether, and 42 ml of a 1Nsodium chloride aqueous solution was added thereto under stirring at 0°C. The mixture was stirred at 0° C. for 30 minutes. The diethyl etherlayer was washed sequentially with a saturated sodium hydrogencarbonateaqueous solution and a saturated sodium chloride aqueous solution andthen dried over anhydrous sodium sulfate. The solvent was distilled offunder reduced pressure, and then the residue was purified by silica gelcolumn chromatography (n-hexane,/ethyl acetate=1/1) to obtain 2.9 g of(2S,3S)-4-benzyloxy-2,3-epoxy-1-butanol as colorless oily substance.

Rf: 0.28 (n-hexane/ethyl acetate=1/1)

Angle of rotation: [α]_(D) ²⁰ -22.7° (C 0.988,CHCl₃)

Mass spectrum (FAB) m/z 195(M⁺ +1)

(b) 2.15 g of (2S,3S)-4-benzyloxy-2,3-epoxy-1-butanol was dissolved in13 ml of dry DMF, and 1.83 g of imidazole and 2 g oftert-butyldimethylchlorosilane were added thereto. The mixture wasstirred at room temperature overnight. The reaction solution was dilutedwith ethyl acetate, washed sequentially with cold 1N hydrochloric acid,water and a saturated sodium chloride aqueous solution and dried overanhydrous sodium sulfate. Then, the solvent was distilled off underreduced pressure, and the residue was purified by silica gel columnchromatography (n-hexane/ethyl acetate=10/1) to obtain 2.3 g of(2S,3S)-4-benzyloxy-2,3-epoxy-1-butanol tert-butyldimethylsilyl ether ascolorless oily substance.

Rf: 0.59 (n-hexane/ethyl acetate=5/1)

Angle of rotation: [α]_(D) ²⁰ -9.0° (C 1.140,CHCl₃)

Mass spectrum (FAB) m/z 441(M⁺ +Cs)

(c) 123 mg of copper iodide was suspended in 2.3 ml of dry THF, and 8 mlof naphthylmethyl magnesium chloride (0.8M diethyl ether solution) wasadded thereto under stirring. The mixture was stirred at the sametemperature for five minutes. Then, 1.0 ml of a dry THF solution of 1 gof (2S,3S)-4-benzyloxy-2,3-epoxy-1-butanol tert-butyldimethylsilyl etherwas added thereto, and the mixture was stirred at room temperature for 1hour. The reaction solution was poured into a saturated ammoniumchloride aqueous solution and extracted with diethyl ether. The extractwas washed seqeuntially with water and a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. Then, thesolvent was distilled off under reduced pressure, and the residue waspurified by silica gel column chromatography (n-hexane/ethylacetate=20/1) to obtain 938 mg of the above identified compound ascolorless oily substance.

Rf: 0.53 (n-hexane/ethyl acetate=5/1)

Angle of rotation: [α]_(D) ²⁰ -21.8° (C 1.120, CHCl₃)

Mass spectrum (FAB) m/z 451(M⁺ +1)

(3) (2R,3R)-4-benzyloxy-3-(1-naphthylmethyl)butan-1,2-diol

910 mg of(2R,3R)-4-benzyloxy-1-tert-butyldimethylsilyloxy-3-(1-naphthylmethyl)-2-butanolwas treated with 7 ml of tetra-n-butylammonium fluoride (1M THFsolution), and stirred at 0° C. for ten minutes and then at roomtemperature for 50 minutes. The reaction solution was diluted withdiethyl ether, and then washed sequentially with a saturated sodiumhydrogencarbonate aqueous solution and a saturated sodium chlorideaqueous solution and dried over anhydrous sodium sulfate. The solventwas distilled off under reduced pressure, and the residue was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=1/1) toobtain 642 mg of the above identified compound as colorless oilysubstance.

Rf: 0.29 (n-hexane/ethyl acetate=1/1)

Angle of rotation: [α]_(D) ²⁰ -42.6° (C 1.187, CHCl₃)

Mass spectrum m/z 337(M⁺ +1)

(4) (2R)-3-benzyloxy-2-(1-naphthylmethyl)propionic acid

740 mg of (2R,3R)-4-benzyloxy-3-(1-naphthylmethyl)butan-1,2-diol wasdissolved in 50 ml of methanol, and 19 ml of an aqueous solution of 568mg of sodium metaperiodate was added thereto under stirring at 0° C. Themixture was stirred at room temperature for 4 hours. The insolubles wereremoved by filtration, and then the solvent was concentrated underreduced pressure. The residue was diluted with a saturated sodiumhydrogencarbonate aqueous solution, and extracted with diethyl ether.Then, the extract was washed with a saturated sodium chloride aqueoussolution and dried over anhydrous sodium sulfate. The solvent wasdistilled off under reduced pressure. 620 mg of(2R)-3-benzyloxy-2-(1-naphthylmethyl)-1-propanal thereby obtained asoily substance, was dissolved in 50 ml of acetone, and Jones' reagentwas added thereto under stirring at 0° C. The mixture was stirred at thesame temperature for 1.5 hours. To the reaction solution, isopropanolwas added for decomposition of the reagent. Then, the insolubles wereremoved by filtration, and the filtrate was concentrated under reducedpressure. The concentrated solution was diluted with ethyl acetate,washed sequentially with water and a saturated sodium chloride aqueoussolution and dried over anhydrous sodium sulfate. Then, the solvent wasdistilled off under reduced pressure, and the residue was purified bysilica gel column chromatography (n-hexane/ethyl acetate=2/1) to obtain457 mg of the above identified compound as colorless oily substance.

Rf: 0.47 (n-hexane/ethyl acetate/acetic acid=1/1/0.5)

Angle of rotation: [α]_(D) ²⁰ -13.2° (C 1.04, CHCl₃)

Mass spectrum m/z 321(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 3.11-3.21(1H,m), 3.33(1H,dd,J=15.2,8.0 Hz),3.57(1H,dd,J=15.2,7.6 Hz), 3.66(2H,d,J=7.2 Hz), 4.51(1H,d,J=16.0 Hz),4.55(1H,d,J=16.0 Hz), 7.24-7.38(7H,m), 7.45-7.55(2H,m), 7.75(1H,d,J=8.0Hz), 7.86(1H,d,J=8.0 Hz), 8.05(1H,d,J=8.0 Hz)

EXAMPLE 54 (2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride

(1) 3-O-benzyl-1,2-O-isopropylidene-α-D-allofuranose

3.0 g of sodium hydride was added to 50 ml of dry DMF, and 31 ml of adry DMF solution of 30.7 g of1,2:5,6-di-O-isopropylidene-α-D-allofuranose was added thereto understirring and cooling with ice. The mixture was stirred at roomtemperature for one hour, and then 14.5 ml of benzyl bromide wasdropwise added thereto under cooling with ice. The mixture was stirredat room temperature overnight. Then, 90 ml of water was added theretounder cooling for crystallization. The crystals were collected byfiltration washed with 50 ml of cold water and then dried to obtain3-O-benzyl derivative 39.1 g (yield: 95%) of slightly yellow crudecrystals.

Then, the crystals was dissolved in 200 ml of 70% acetic acid, and thereaction was conducted at 37° C. for seven hours. The reaction solutonwas neutralized with aqueous sodium carbonate (200 g/300 ml) undercooling with ice and extracted with ethyl acetate (300 ml×1 time, 150ml×1 time). The extract was washed with water (200 ml) and then with asaturated sodium chloride aqueous solution (200 ml) and then dried overanhydrous sodium sulfate. The filtrate was concentrated under reducedpressure to obtain the above identified compound 54.5 g of slightlyyellow syrup (yield: 94%).

NMR (300 MHz, CHCl₃): δppm: 1.37(3H,s), 1.60(3H,s), 3.70(2H,s)3.93(1H,dd,J=4.4,8.7 Hz), 4.01(1H,m), 4.12(1H,dd,J=3.2,8.9 Hz),4.56(1H,d,J=11.2 Hz), 5.77(1H,d,J=3.6 Hz), 7.3-7.4(5H,m)

Rf: 0.2 (chloroform/methanol=30/1)

(2) 3-O-benzyl-1,2-O-isopropylidene-α-D-ribo-pentodialdo-1,4-furanose

34.5 g of 3-O-benzyl-1,2-O-isopropylidene-α-D-allofuranose was dissolvedin 280 ml of ethanol/water (7/1), and a sodium methaperiodate aqueoussolution (25 g/210 ml) was dropwise added thereto. The mixture wasstirred at room temperature for 1.5 hours, and then the precipitatedinorganic salts were separated by filtration. The salt thereby separatedwas washed with a samll amount of ethanol. The washing solution and thefiltrate were put together and concentrated under reduced pressure. Thesyrup thereby obtained was dissolved in 300 ml of ethyl acetate andwashed with 100 ml of water and then with 100 ml of a sodium chlorideaqueous solution. The ethyl acetate layer was dried over anhydrousmagnesium sulfate and then concentrated under reduced pressure. Thesyrup thereby obtained was dissolved in diethyl ether and the diethylether solution was concentrated again and dried under reduced pressureto obtain 32.6 g of the above identified compound as slightly yellowcrude syrup. This syrup could be used as a starting material for Wittigreaction in the following step as it was.

Rf: 0.44 (chloroform/methanol=30/1)

(3)3-O-benzyl-5-cyclohexylidene-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranose

82.7 g of cyclohexyltriphenylphosphonium bromide was suspended understirring in 600 ml of 1,2-dimethomyethane purified by distillation. Thereaction solution was sealed under an argon atmosphere, and 130 ml ofn-butyl lithium (n-hexane solution, 1.5N) was dropwise added thereto atroom temperature. The mixture was stirred for one hour to form a reddishbrown ylide. The reactor was cooled with ice, and a 1,2-dimethoxyethanesolution (36 g/70 ml) of3-O-benzyl-1,2-O-isopropylidene-α-D-ribopentodialdo-1,4-furanose wasadded thereto over a period of 30 minutes. The temperature was returnedto room temperature, and the reaction solution was stirred for 18 hours.Then, the precipitated salt was separated by filtration. The saltthereby separated was washed with a small amount of benzene. To thecombined filtrate, 100 ml of water was added to decompose the excessylide. The reaction solution was distillated off, and the residuethereby obtained was dissolved in 300 ml of benzene. The benzenesolution was washed with 130 ml of water and then with 150 ml of asaturated sodium chloride aqueous solution. Then, the benzene layer wasdried over anhydrous magnesium sulfate. The dried benzene layer wasconcentrated under reduced pressure, and the concentrate was purified bysilica get column chromatography (n-hexane/ethyl acetate=8/1). Theeluted fractions containing the desired compound were put together,concentrated under reduced pressure and dried to obtain 28.9 g (yield:64%) of white solid. The solid was recrystallized from 50 ml n-hexane toobtain 27.2 g (yield: 61%) of columnar crystals.

NMR (300 MHz, CDCl₃): δppm: 1.35(3H,s), 1.58(6H,m), 1.64(3H,s),2.13(2H,br), 2.29(2H,br), 3.46(1H,dd,J=4.4,8.8 Hz), 4.53(1H,t,J=4.0 Hz),4.63(1H,d,J=12.4 Hz), 4.73(1H,d,J=12.4 Hz), 4.82(1H,t,J=8.9 Hz),5.02(1H,dd,J=1.5,8.7 Hz), 5.70(1H,d,J=3.6 Hz), 7.29-7.35(5H,m)

Melting point: 62°-64° C.

Angle of rotation: [α]_(D) ²⁰ =-7.2° (C=0.97, CHCl₃)

IR: νcm⁻¹ : 2930, 2850, 1460, 1390, 1380, 1250, 1220, 1200, 1170, 1130,1120, 1090, 1030, 1000, 890, 870, 730

Elemental analysis: Calculated value: C: 73.23, H: 8.19; Measured valueC: 73.28, H: 8.12.

(4) Methyl 2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-α-D-ribofuranoside andmethyl 2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-β-D-ribofuranoside

27.0 g of3-O-benzyl-5-cyclohexylidene-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranosewas dissolved in 230 ml of ethanol, and Raney nickel (W1) in about 10 mlof ethanol was added thereto. The stirring was continued under ahydrogen atmospheric pressure. 4.5 hours later, the catalyst wasseparated by filtration on Celite, and the filtrate was concentratedunder reduced pressure and dried under reduced pressure to obtain 28.4 gof 3-O-benzyl-5-cyclohexyl-5-deoxy-1,2-O-isopropylidene-α-D-ribofuranoseas transparent syrup. Then, the syrup was dissolved in 66 ml of drymethanol. 66 ml of 10% dry methanol hydrochloride was added thereto andreacted therewith at room temperature under sealing for 66 hours. Then,100 ml of methanol was added to the reaction solution and diluted it.500 ml of an anion exchange resin Amberlite (IRA-400, OH⁻) was graduallyadded to the reaction solution for neutralization. The resin was removedby filtration, and then the reaction solution was concentrated underreduced pressure. The syrup thereby obtained was azeotropicallyconcentrated to dryness from the diethyl ether solution and from thebenzene solution under reduced pressure to obtain 24.7 g of methyl3-O-benzyl-5-cyclohexyl-5-deoxy-α(or β)-D-ribofuranoside as yellowsyrup. (Rf: 0.311, silica gel plate, n-hexane/ethyl acetate=3/1)

Then, the syrup was dissolved in 45 ml of dry DMF without purification,and the solution was added under cooling with ice to 30 ml of a dry DMFsolution containing 1.9 g of sodium hydride prepared separately. Thetemperature was returned to room temperature, and the mixture wasstirred for 30 minutes and cooled with ice. 9.3 ml of benzyl bromide wasadded thereto and the mixture was stirred at room temperature overnight.Then, the reaction solution was dissolved in 400 ml of ethyl acetate,and the solution was washed sequentially with 300 ml of water and with300 ml of a saturated sodium chloride aqueous solution. The organiclayer was dried over anhydrous sodium sulfate and then concentratedunder reduced pressure. The concentrate was purificated by silica gelcolumn chromatography (n-hexane/ethyl acetate=8/1-6/1) to obtain 3.55 gof methyl 2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-α-D-ribofuranoside and27.6 g of methyl 2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-β-D-ribofuranosideas colorless transparent syrup.

α-anomer:

NMR (300 MHz, CDCl₃): δppm: 0.85(2H,m), 1.1-1.4(6H,m), 1.6-1.8(5H,m),3.45(3H,s), 3.50(1H,dd,J=3.6,6.8 Hz), 3.76(1H,dd,J=4.0,6.8 Hz),4.18(1H,m), 4.59(1H,d,J=12.7 Hz), 4.63(1H,d,J=12.2 Hz), 4.68(1H,d,J=12.5Hz), 4.74(1H,d,J=13.1 Hz), 4.83(1H,d,J=4.5 Hz), 7.28-7.40(10H,m)

Rf: 0.44 (n-hexane/ethyl acetate=3/1)

IR: νcm⁻¹ : 3050, 2930, 2850, 1510, 1460

β-anomer:

NMR (300 MHz, CDCl₃): ppm: 0.9(2H,m), 1.1-1.3(3H,m), 1.4-1.6(3H,m),1.6-1.85(5H,m), 3.31(3H,s), 3.77(1H,dd,J=4.5,7 Hz), 3.82(1H,dd,J=1,4.5Hz), 4.22(1H,m), 4.41(1H,d,J=12 Hz), 4.55(1H,d,J=12 Hz), 4.57(1H,d,J=12Hz), 4.68(1H,d,J=12 Hz), 4.87(1H,s)

Rf: 0.60 (n-hexane/ethyl acetate=3/1)

IR: νcm⁻¹ : 3040, 2930, 2850, 1500, 1460

(5) (2S,3R,4R)-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentan-4-ol

30.8 g of the mixture of methyl2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-α-D-ribofuranoside and its β-anomerobtained step (4), was dissolved in 600 ml of acetic acid/hydrochloricacid/water (9/1/2), and reacted at 20° C. for 10 hours and then at 6° C.for 14 hours. The reaction solution was diluted with 1 liter of tolueneand washed sequentially with water (400 ml×2 times), with a 4% sodiumhydrogencarbonate aqueous solution (500 ml) and with saturated sodiumchloride aqueous solution (500 ml). The organic layer was dried overanhydrous magnesium sulfate and then concentrated under reduced pressureto obtain 2,3-di-O-benzyl-5-cyclohexyl-5-deoxy-D-ribofuranose as yellowsyrup. (Rf: 0.38, silica gel plate, solvent: hexane/ethyl acetate=3/1)

Then, the product was dissolved in 500 ml of methanol. 41.7 g ofmorpholine hydrochloride was added thereto and dissolved. A methanolsolution of sodium cyanoborohydride (8.49 g/100 ml) was added thereto,and then the mixture was stirred. The mixture was stirred at roomtemperature for 39 hours, and then the reaction solution wasconcentrated under reduced pressure. The product was dissolved in 1liter of benzene/ethyl acetate (4/6), and the mixture was washed withwater (300 ml×2 times) with a saturated sodium chloride aqueous solution(300 ml). The organic layer was dried over anhydrous magnesium sulfate,and then concentrated under reduced pressure. The purification by silicagel column chromatography (chloroform/ethyl acetate=4/1) and the dryingunder reduced pressure were conducted to obtain 31.7 g of the aboveidentified compound as white solid (yield: 90%).

NMR (300 MHz, 55° C., CDCl₃): δppm: 0.85(2H,m), 1.1-1.3(5H,m),1.44(1H,m), 1.55-1.8(5H,m), 2.39(1H,dd,J=2.5,13.1 Hz), 2.51(4H,m),3.02(1H,dd,J=8.9,13.1 Hz), 3.59(1H,dd,J=1.4,5.3 Hz), 3.66(4H,m),3.77(2H,m), 4.56(1H,d,J=12.2 Hz), 4.59(1H,d,J=12.2 Hz), 4.63(1H,d,J=11.7Hz), 4.76(1H,d,J=11.7 Hz), 7.2-7.4(10H,m)

IR:

νcm⁻¹ : 3220(br), 2930, 2850, 1460, 1120, 1070, 1030

Melting point: 54°-56° C.

Angle of rotation: [α]_(D) ²⁰ =+31.0° (C=1.09, CHCl₃)

Elemental analysis: Calculated value: C: 74.48, H: 8.84, N: 3.00;Measured value: C: 74.52, H: 8.87, N: 2.92.

(6) (2S,3R,4S)-4-azide-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentane

27.7 g of(2S,3R,4R)-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentan-4-ol wasdissolved in 200 ml of dry THF, and 24.9 g of triphenylphosphine wasadded thereto and dissolved. Then, the reaction solution was stirred at-20° C. under cooling. To the reaction solution, 14.9 mg of diethylazodicarboxylate and 20.5 ml of DPPA were dropwise added thereto,respectively. A few minutes later, the reaction solution was stirred at20° C. 24 hours later, the reaction solution was concentrated underreduced pressure, the syrup thereby obtained was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=5/1) to obtain 12.7 g(yield: 43%) of desired colorless transparent syrup.

NMR (300 MHz, CDCl₃): δppm: 0.89(2H,m), 1.1-1.5(5H,m), 1.7(6H,m),2.37(2H,ddd,J=4.6,4.7,11.3 Hz), 2.59(2H,m), 2.65(2H,m),3.56(1H,ddd,J=3.4,4.0,10.1 Hz), 3.64(1H,dd,J=3.1,6.6 Hz), 3.67(4H,m),3.74(1H,m), 4.58(1H,d,J=11.1Hz), 4.69(1H,,d,J=11.1Hz), 4.73(1H,d,J=11.5Hz), 4.78(1Hd,J=11.5 Hz), 7.28-7.38(10H,m)

IR: νcm⁻¹ : 2930, 2850, 2110, 1750, 1740, 1500, 1460

Mass spectrum (FAB) m/z 493(M⁺ +1)

(7) (2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride

80 mg of(2S,3R,4S)-4-azide-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentane wasdissolved in 2 ml of ethanol, and 0.2 ml of 2N hydrochloric acid wasadded for acidification. Hydrogen gas was continuously blown thereintoin the presence of a palladium black catalyst. Two hours later, thecatalyst was separated on celite by filtration, and the filtrate wasconcentrated under reduced pressure. The residue was concentrated underreduced pressure in the form of a mixed solution of ethanol/benzene andazeotropically dried. The dried solid was recrystallized fromdichloromethane/diethyl ether to obtain 52 mg (yield: 90%) of whitecrystals.

¹ H-NMR (300 MHz, CDCl₃, free salt): δppm: 0.95(2H,m), 1.23(3H,m),1.43(2H,m), 1.57(1H,m), 1.72(5H,m), 2.55(2H,m), 3.40(1H,m), 3.50(1H,brdd,J=1.5,7.0 Hz), 3.70(4H,m), 3.88(1H,m), 4.26(4H,br)

¹³ C-NMR (75 Hz, CDCl₃): -D₂ O, hydrochloride): δppm: 25.8(2C), 26.2,32.6, 33.1, 33.2, 37.2, 48.9, 52.4, 53.5, 60.8, 63.5, 63.6, 65.1, 69.9

EXAMPLE 55(2S,3R,4R)-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentan-4-ol

(1) 1,4-pentadien-3-ol

To 400 ml of a THF solution of 0.98M vinyl magnesium bromide, 11.0 ml ofmethyl formate was dropwise added over a period of 1 hour at atemperature of from 0° to 5° C. After completion of the dropwiseaddition, 100 ml of a saturated ammonium chloride aqueous solution wasimmediately added thereto, and the mixture was extracted with THF. TheTHF layer was dried over anhydrous magnesium sulfate, and then thesolvent was distilled off under reduced pressure (100 mmHg). The residuewas subjected to distillation under reduced pressure to obtain 9.6 g ofthe above identified compound as colorless liquid.

Rf: 0.52 (n-hexane/ethyl acetate=2/1)

Boiling point: 55°-57° C./78 mmHg)

(2) (2R,3S)-1,2-epoxypent-4-ene-3-ol

7 g of molecular sieves (3A, powder) were suspended in 500 ml ofdichloromethane, and 10.2 g of tetraisopropyl orthotitanate and 8.8 g ofdiethyl L-(+)-tartarate were added thereto under an argon atmosphere at-30° C. Then, 40.5 ml of tert-butylhydroperoxide (5M dichloromethanesolution, treated with molecular sieves 4A for 30 minutes before thedropwise addition) was dropwise added over a period of 10 minutes at thesame temperature. The mixture was stirred at the same temperature for 10minutes. A dichloromethane solution of 10 g of 1,4-pentadien-3-ol wasdropwise added thereto over a period of 20 minutes. The mixture was leftto stand at -20° C. for ten days, and then, 500 ml of acetone containing10.5 ml of water was added to the reaction solution at -20° C. Themixture was stirred at room temperature for three hours. Then, theinsoluble substances were removed by filtration, and the filtrate wasconcentrated under reduced pressure. The residual solution was subjectedto distillation under reduced pressure, and the eluted fractions of aboiling point of 30°-60° C./18 mmHg (first fraction) and a boiling pointof 60°-73° C./18 mmHg (second fraction) were collected. Each fractionwas purified by silica gel column chromatography (n-pentane/diethylether=1/1) to obtain 2.3 g and 5.4 g of the above identified compound ascolorless liquid, respectively.

Rf: 0.27 (n-hexane/ethyl acetate=2/1)

Angle of rotation: [α]_(D) ²⁰ =+57.3° (C=0.964, CHCl₃)

(3)(2R,3S)-3-benzyloxy-2-tert-butyldimethylsilyloxy-1-cyclohexyl-4-pentene

(a) 428 mg of sodium hydride (60% in oil) was suspended in 8 ml of THF,and a THF solution (5 ml) of 970 mg of (2R,3S)-1,2-epoxypent-4-ene-3-olwas dropwise added thereto under an argon atmosphere at -10° C. Themixture was stirred at room temperature for 20 minutes. Then, 360 mg oftetra-n-butylammonium iodide and 1.27 ml of benzyl bromide were addedthereto at -10° C. The mixture was stirred at room temperature for twohours, and then poured into a saturated ammonium chloride aqueoussolution and extracted with ethyl acetate. The ethyl acetate layer wasdried over anhydrous magnesium sulfate, and the solvent was distilledoff. The residue was purified by silica gel column chromatography(n-hexane/ethyl acetate=10/1) to obtain 1.7 g of(2R,3S)-3-benzyloxy-1,2-epoxy-4-pentene as colorless oily substance.

Rf: 0.49 (n-hexane/ethyl acetate=4/1)

(b) 146 mg of copper (I) iodide was suspended in THF, and 3.85 ml ofcyclohexyl magnesium chloride (2M diethyl ether solution) was addedthereto under an argon atmosphere at -78° C. The mixture was stirred atthe same temperature for ten minutes. Then, a THF solution (5 ml) of 969mg of (2R,3S)-3-benzyloxy-1,2-epoxy-4-pentene was dropwise added theretoover a period of 10 minutes at -78° C. The mixture was stirred at -10°C. for two hours, and then poured into a saturated ammonium chlorideaqueous solution and extracted with ethyl acetate. The extract layer waswashed with a saturated sodium chloride aqueous solution and dried overanhydrous magnesium sulfate. The solvent was distilled off under reducedpressure to obtain 1.2 g of(2R,3S)-3-benzyloxy-1-cyclohexyl-4-penten-2-ol as slightly brown oilysubstance. This alcohol was dissolved in DMF, and 923 mg oftert-butyldimethylsilyl chloride, 312 mg of 4 -dimethylaminopyridine and923 μl of triethylamine were added thereto at 0° C. The mixture wasstirred at room temperature overnight. Then, water and ethyl acetatewere added to the reaction solution, and the organic layer wasseparated. The organic layer was washed sequentially with 1Nhydrochloric acid, with 4% sodium hydrogencarbonate, with water and witha saturated sodium chloride aqueous solution and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure,and the residue was purified by silica gel column chromatography(n-hexane/benzene=10/1) to obtain 1.3 g of the above identified compoundas colorless oily substance.

Rf: 0.53 (n-hexane/benzene=5/1)

Angle of rotation: [α]_(D) ²⁰ =+28.9° (C=0.944, CHCl₃)

(4)(2S,3R,4R)-3-benzyloxy-4-tert-butyldimethylsilyloxy-5-cyclohexyl-1,2-epoxypentane

(a) 1.27 g of 4-penten-2,3-diol having a protected hydroxyl groupobtained in step (3), was dissolved in a solvent mixture of acetone (12ml)/water (1.2 ml), and 42 mg of osmium tetraoxide and 790 mg ofN-methylmorpholine N-oxide were added thereto. The mixture was stirredat room temperature overnight. Then, 35 ml of a saturated sodiumhydrogen sulfate aqueous solution was added thereto and the mixture wasextracted with ethyl acetate. The organic layer was washed with asaturated sodium chloride aqueous solution and the solvent was distilledoff under reduced pressure. The residue was purified by silica gelcolumn chromatography (n-hexane/ethyl acetate=2/1) to obtain 1.12 g of(2S,3R,4R)-3-benzyloxy-4-tert-butyldimethylsilyloxy-5-cyclohexylpentan-1,2-diolas colorless oily substance.

Rf: 0.43 (n-hexane/ethyl acetate=2/1)

(b) The diol obtained in step (a) was dissolved in 3 ml ofdichloromethane, and 46 μl of methanesulphonyl chloride and 94 μl oftriethylamine were dropwise added thereto at 0° C. The mixture wasstirred at room temperature for 20 minutes. Then, ethyl acetate wasadded thereto. The mixture was washed sequentially with water, with 1Nhydrochloric acid, with a 4% sodium hydrogencarbonate aqueous solution,with water and with a saturated sodium chloride aqueous solution anddried over anhydrous magnesium sulfate. Then, the solvent was distilledoff under reduced pressure. The residue was dissolved in 4 ml ofmethanol, and 124 mg of potassium carbonate was added thereto at 0° C.The mixture was stirred at room temperature overnight. Then, 78 μl ofacetic acid, water and ethyl acetate were added to the reactionsolution. The organic layer was separated, washed with a saturatedsodium chloride aqueous solution and then dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure, and theresidue was purified by silica gel column chromatography (n-hexane/ethylacetate=4/1) to obtain 125 mg of the above identified compound ascolorless oily substance.

Rf: 0.76 (n-hexane/ethyl acetate=4/1)

NMR (300 MHz, CDCl₃): δppm: 0.06(3H,s), 0.08(3H,s), 0.90(9H,s),0.75-1.05(1H,m), 1.10-1.70(12H,m), 2.69(1H,dd,J=2.7,5.4 Hz),2.75(1H,dd,J=3.9,5.4 Hz), 3.12(1H,ddd,J=2.7,3.9,5.1 Hz),3.23(1H,dd,J=2.4,5.1 Hz), 3.98(1H,ddd,J=2.4,4.5,8.3 Hz), 4.60(2H,s),7.23-7.38(5H,m)

(5) (2S,3R,4R)-2,3-dibenzyloxy-5-cyclohexyl-1-morpholinopentan-4-ol

(a) 122 mg of the epoxy compound obtained in step (4) was dissolved in1.5 ml of methanol, and 32 μl of morpholine was added thereto. Themixture was heated at a temperature of from 75° to 80° C. for two hoursand further at 60° C. overnight. The reaction solution was concentratedunder reduced pressure to dryness, and the residue was purified bysilica gel column chromatography (n-hexane/ethyl acetate=4/1) to obtain139 mg of(2S,3R,4R)-3-benzyloxy-4-tert-butyldimethylsilyloxy-5-cyclohexyl-1-morpholinopentan-2-olas colorless oily substance.

Rf: 0.11 (n-hexane/ethyl acetate=4/1)

NMR (300 MHz, CDCl₃): δppm: 0.10(3H,s), 0.12(3H,s), 0.75-1.05(2H,m),0.91(9H,s), 1.01-1.85(11H,m), 2.30-2.47(3H,m), 2.55-2.72(3H,m),3.41(1H,dd,J=1.8,7.1 Hz), 3.62-3.75(5H,m), 4.16(1H,ddd,J=1.8,3.3,8.7Hz), 4.55(1H,d,J=11.7 Hz), 4.87(1H,d,J=11.7 Hz), 7.25-7.40(5H,m)

(b) 12 mg of sodium hydride (60% in oil) was suspended in 0.5 ml of THF,and a THF solution (0.5 ml) of 135 mg of the amino alcohol obtained instep (a) was dropwise added thereto under an argon atmosphere at -20° C.The mixture was stirred at room temperature for one hour. Then, 11 mg oftetra-n-butylammonium iodide and 36 μl of benzyl bromide were addedthereto. The mixture was stirred at room temperature overnight. Then,the reaction solution was poured into a saturated ammonium chlorideaqueous solution and the mixture was extracted with ethyl acetate. Theextract was dried over anhydrous magnesium sulfate. Then, the solventwas distilled off under reduced pressure, and the residue was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=8/1) toobtain 30 mg of(2S,3R,4R)-2,3-dibenzyloxy-4-tert-butyldimethylsilyloxy-5-cyclohexyl-1-morpholinopentaneas colorless oily substance. Further, 103 mg of the starting materialwas recovered.

Rf: 0.70 (n-hexane/ethyl acetate=2/1)

NMR (300 MHz, CDCl₃): δppm: 0.07(3H,s), 0.10(3H,s), 0.70-1.00(2H,m),0.92(9H,s), 1.10-1.78(11H,m), 2.34-2.44(2H,m), 2.50-2.76(4H,m),3.59(1H,dt,J=2.4,6.5 Hz), 3.64-3.76(5H,m), 4.14(1H,m), 4.52(1H,d,J=11.4Hz), 4.61(1H,d,J=11.4 Hz), 4.70(1H,d,J=11.4 Hz), 4.87(1H,d,J=11.4 Hz),7.20-7.40(10H,m)

(c) The protected triol obtained in step (b) was dissolved in 0.2 ml ofTHF, and 80 μl of a THF solution of 1M tetra-n-butylammonium chloridewas added thereto. The mixture was stirred at room temperature. Further,two hours later, 160 μl of a THF solution of 1M tetra-n-butylammoniumchloride was added thereto and four hours later, 200 μl of the THFsolution was added thereto. The mixture was stirred at room temperatureovernight. Diethyl ether was added to the reaction solution. The mixturewas washed with water and with a saturated sodium chloride aqueoussolution and dried over anhydrous magnesium sulfate. Then, the solventwas distilled off under reduced pressure, and the residue was purifiedby silica gel column chromatography (n-hexane/ethyl acetate=1/1) toobtain 15.5 mg of the above identified compound as colorless solid.

Rf: 0.64 (n-hexane/ethyl acetate=2/1)

This compound completely agreed with a product derived from1,2:5,6-diisopropylidene-2-D-allofuranose in a 300 MHz NMR analysis.

EXAMPLE 56(2S,3R,4S)-4-{L-N-[(2S)-2-benzyl-3-furfurylsulfonylpropionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 1.2 g of (2S,3S)-4-benzyloxy-2,3-epoxy-1-butanaltert-butyldimethylsilyl ether obtained in Example 53 was subjected toGrignard reaction by using benzyl magnesium bromide (0.8M diethyl ethersolution) in the same manner as in Example 53 to obtain 975 mg of(2R,3R)-3-benzyl-4-benzyloxy-1-tert-butyldimethylsilyloxy-2-butanal ascolorless oily substance.

Then, the removal of the silyl group by 5 ml of tetra-n-butylammoniumfluoride (1M THF solution) was conducted in the same manner as inExample 53. Then the product was converted to an aldehyde by using 625mg of sodium metaperiodate and subjected to chromic acid oxidation(Jones' reagent) to obtain 427 mg of (2R)-2-benzyl-3-benzyloxypropionicacid.

Rf: 0.57 (n-hexane/ethyl acetate/acetic acid=6/6/0.2).

Angle of rotation: [α]_(D) ²⁶ =-4.8° (C=0.765, CHCl₃)

Mass spectrum (FAB) m/z 293(M⁺ +Na), 271(M⁺ +1)

(b) 420 mg of (2R)-2-benzyl-3-benzyloxypropionic acid was dissolved in5.5 ml of ethanol, and hydrogenated at an ordinary temperature under anatmospheric pressure for two hours in the presence of palladium black.The insolubles were removed by filtration, and then the solvent wasdistilled off under reduced pressure to obtain 290 mg of(2R)-2-benzyl-3-hydroxypropionic acid as colorless oily substance.

Rf: 0.24 (n-hexane/ethyl acetate/acetic acid=6/6/0.2)

Angle of rotation: [α]_(D) ²⁶ =+4.9° (C=0.853, CHCl₃)

Mass spectrum (FAB) m/z 203(M⁺ +Na), 181(M⁺ +1)

(c) 274 mg of (2R)-2-benzyl-3-hydroxypropionic acid was dissolved in 2ml of dry DMF, and subjected to coupling raction with 322 mg ofL-norleucine tert-butyl ester by a DCC-HOBT method in the same manner asin Example 47 to obtain 306 mg offL-N-[(2S)-2-benzyl-3-hydroxypropionyl]norleucine tert-butyl ester aswhite solid.

Rf: 0.25 (n-hexane/ethyl acetate=2/1)

(d) 68 mg of L-N-[(2S)-2-benzyl-3-hydroxypropionyl]norleucine tert-butylester was subjected to tosylation (P-toluenesulfonyl chloride). Then,the product was substituted with furfurylmercaptan to convert to thefurfurylthio ether. Then, the furfurylthio ether was oxidized byhydrogen peroxide/sodium tungstate to the sulfone compound, and thesulfone compound was treated with TFA to obtain 60 mg ofL-N-[(2S)-2-benzyl-3-furfurylsulfonylpropionyl]norleucine as colorlessoily substance.

Rf: 0.22 (n-hexane/ethyl acetate/acetic acid=6/6/0.2)

(e) 60 mg of L-N-[(2S)-2-benzyl-3-furfurylsulfonylpropionyl]norleucinewas dissolved in 0.4 ml of dry DMF, and subjected to coupling reactionconducted in the same manner as in Example 47 with 62 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride by a DPPA method to obtain 72 mg of the above identifiedcompound as white powder.

Rf: 0.40 (chloroform/methanol=20/1)

Mass spectrum (FAB) m/z 690(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.79-1.06(3H,m), 1.06-1.94(19H,m),2.40-3.15(10H,m), 3.39-3.85(7H,m), 4.17-4.31(4H,m), 5.90(1H,d,J=7.9 Hz),5.98(1H,d,J=8.7 Hz), 6.41(1H,d,J=0.8 Hz), 6.46(1H,d,J=0.8 Hz),7.18-7.52(5H,m)

EXAMPLE 57(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-[(5,6,7,8-tetrahydro-1-naphthyl)methyl]propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) 107 mg ofL-N-[(2R)-3-benzyloxy-2-(1-naphthylmethyl)propionyl]norleucinetert-butyl ester was dissolved in 2 ml of ethanol and hydrogenated at aordinally temperature under an atmospheric pressure by an addition ofpalladium black. The catalyst was removed by filtration, and then thesolvent was distilled off to obtain 89 mg ofL-N-{(2R)-3-hydroxy-2-[(5,6,7,8-tetrahydro-1-naphthyl)methyl]propionyl}norleucinetert-butyl ester as colorless oily substance.

Rf: 0.33 (n-hexane/ethyl acetate=2/1)

(b) 87 mg ofL-N-{(2R)-3-hydroxy-2-[(5,6,7,8-tetrahydro-1-naphthyl)methyl]propionyl}norleucinetert-butyl ester was subjected to tosylation in the same manner asExample 1, and then converted to the thio compound by usingethylmercaptan. Then, the thio compound was oxidized to the sulfonecompound and treated with TFA to obtain 61 mg ofL-N-{(2S)-3-ethylsulfonyl-2-[(5,6,7,8-tetrahydro-1-naphthyl)methyl]propionyl}norleucineas colorless oily substance. This compound was subjected to couplingreaction in the same manner as in Example 3 with 39 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride by a DPPA method to obtain 27 mg of the above identifiedcompound as white powder.

Rf: 0.42 (chloroform/methanol=20/1)

Mass spectrum m/z 692(M⁺ +1)

EXAMPLE 58N-[(2S,3R,4S)-4-[L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl]amino-5-cyclohexyl-2,3-dihydroxypentyl]piperidineN-oxide

10.6 mg of(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-piperidino-2,3-pentanediolobtained in Example 17, was dissolved in 0.5 ml of methanol. 50 μl of a30% hydrogen peroxide aqueous solution and 2 mg of sodium tungstatedehydrate were added thereto for oxidation in the same manner as inExample 50 to obtain 11.4 mg of the above identified compound as whitesolid.

Rf: 0.39 (chloroform//methanol=10/1)

Mass spectrum m/z 702(M⁺ +1)

EXAMPLE 59N-[(2S,3R,4S)-4-[L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl]amino-5-cyclohexyl-2,3-dihydroxypentyl]-N-methylmorpholinonium iodide

8.8 mg of(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediolwas dissolved in 0.3 ml of dry methanol, and 0.3 ml of methyl iodide wasadded thereto. The mixture was refluxed under heating at 50° C. forthree hours. The solvent was distilled off under reduced pressure, andthe residue was treated with acetone/n-hexane to obtain 8.4 mg of theabove identified compound as slightly yellow solid.

Rf: 0.10 (chloroform/methanol=20/1)

Mass spectrum (FAB) m/z 702(M⁺ -I)

EXAMPLE 60(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(3-tolylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) (2R)-3-hydroxy-2-(3-tolylmethyl)propionic acid

(a) 325 mg of (2S,3S)-4-benzyloxy-2,3-epoxy-1-butanoltert-butyldimethylsilyl ether obtained in Example 53, was subjected toGrignard reaction in the same manner as in Example 53 by using3-tolylmethyl magnesium bromide (0.8M diethyl ether solution). Theproduct was purificated by silica gel column chromatography to obtain210 mg of(2R,3R)-4-benzyloxy-1-tert-butyldimethylsiloxy-3-(3-tolylmethyl)-2-butanolas colorless oily substance.

(b) Then, 328 mg of (2R,3R-benzyloxy-1-tert-butyldimethylsilyloxy-3-(3-tolylmethyl)-2-butanol wassubjected to removal of the silyl group with 1.4 ml oftetra-n-butylammonium fluoride (1M THF solution). The product wasconverted to the aldehyde by using 168 mg of sodium metaperiodate, andthe aldehyde was subjected to chromic acid oxidation (Jones' reagent) toobtain 177 mg of (2R)-3-benzyloxy-2-(3-trimethyl)propionic acid ascolorless oily substance.

(c) 157 mg of the compound obtained in step (b) was dissolved inethanol, and hydrogenated at a ordinary temperature under an atmosphericpressure in the presence of palladium balck to obtain 108 mg of theabove identified compound as colorless oily substance.

(2) L-N-[(2S)-3-ethylsulfonyl-2-(3-tolylmethyl)propionyl]norleucine

(a) 89 mg of the compound obtained in step (1) was dissolved in dry DMF,and subjected to coupling reaction with 102 mg of L-norleucinetert-butyl ester by a DCC-HCBT method to obtain 144 mg ofL-N-[(2R)-3-hydroxy-2-(3-tolylmethyl)propionyl]norleucine tert-butylester as colorless oily substance.

(b) 71 mg of the compound obtained in step (a) was subjected totosylation in pyridine by using p-toluenesulfonyl chloride. Then, theproduct was subjected to substitution reaction withethylmercaptan/sodium hydride to obtain 46 mg ofL-N-[(2S)-3-ethylthio-2-(3-tolylmethyl)propionyl]norleucine tert-butylester as colorless oily substance.

(c) The compound obtained in step (b) was sulfonated in methanol withaqueous hydrogen peroxide/sodium tungstate to convert from the sulfideto the sulfone, and the sulfone compound was treated with TFA indichloromethane to obtain 38 mg of the above identified compound ascolorless oily substance.

(3)(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(3-tolylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

38 mg of the compound of step (2) was dissolved in 0.3 ml of dry DMF andsubjected to coupling reaction with 48 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride by a DPPA method. The product was purified by silica gelcolumn chromatography (chloroform/methanol=100/1) to obtain 32 mg of theabove identified compound as colorless solid.

Rf: 0.50 (chloroform/methanol=10/1)

Mass spectrum m/z 652(M⁺ +1)

NMR (300 MHz, CDCl₃): δppm: 0.79-1.35(5H,m), 1.40-1.86(20H,m),2.33(3H,s), 2.42-3.28(12H,m), 3.37-3.53(3H,m), 3.58-3.75(4H,m),4.19-4.31(2H,m), 4.58(1H,br s), 6.03(1H,d,J=9 Hz), 6.14(1H,d,J=6 Hz),6.97-7.10(3H,m), 7.17-7.23(1H,m)

EXAMPLE 61(2S,3R,4S)-4-{L-N-[(2S)-3-ethylsulfonyl-2-(2-tolylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(1) (2R)-3-hydroxy-2-(2-tolylmethyl)propionic acid

(a) 351 mg of (2S,3S)-4-benzyloxy-2,3-epoxy-1-butanoltert-butyldimethylsilyl ether obtained in Example 53, was subjected toGrignard reaction in the same manner as in Example 53 by using2-tolylmethyl magnesium bromide (0.8M diethyl ether solution). Theproduct was purificated by silica gel column chromatography to obtain210 mg of(2R,3R)-4-benzyloxy-1-tert-butyldimethylsilyloxy-3-(2-tolylmethyl)-2-butanolas colorless oily substance.

(b) Then, 266 mg of(2R,3R)-4-benzyloxy-1-tert-butyldimethylsilyloxy-3-(2-tolylmethyl)-2-butanolwas subjected to removal of the silyl group in the same manner as inExample 60 with tetra-n-butylammonium fluoride (1N THF solution). Theproduct was converted to the aldehyde by using sodium methaperiodate,and the aldehyde was subjected to chromic acid oxidation by Jones'reagent. Then, the carboxylic acid thereby obtained was hydrogenated bypalladium balck catalyst at a ordinally temperature under an atmosphericpressure to obtain 88 mg of the above identified compound as colorlessoily substance.

(2)(2S,3R,4S)-4-{L-N-1(2S)-3-ethylsulfonyl-2-(2-tolylmethyl)propionyl]norleucyl}amino-5-cyclohexyl-1-morpholino-2,3-pentanediol

(a) The compound of step (1) was subjected to coupling reaction in thesame manner as in Example 60 with L-norleucine tert-butyl ester by aDCC-HOBT method. The product was subjected to tosylation withp-toluenesulfonyl chloride to obtain the tosyl compound. The tosylcompound was converted to the ethylsulfide by ethylmercaptan/sodiumhydride. The ethylsulfide was oxidized to the sulfone compound by usingaqueous hydrogen peroxide/sodium tungstate. The sulfone compound wastreated with THF in dichloromethane to convert toL-N-[(2S)-3-ethylsulfonyl-2-(2-tolylmethyl)propionyl]norleucine.

(b) 14.1 mg of the carboxylic acid obtained in step (a) was subjected tocoupling reaction with 19.3 mg of(2S,3R,4S)-4-amino-5-cyclohexyl-1-morpholino-2,3-pentanedioldihydrochloride by a DPPA method to obtain 6.3 mg of the aboveidentified compound as colorless solid.

NMR (300 MHz, CDCl₃): δppm: 0.75-1.00(6H,m) 1.07-1.95(19H,m), 2.32(3H,s)2.38-3.12(11H,m), 3.32-3.72(8H,m), 4.16-4.27(2H,m), 5.96(1H,d,J=9 Hz),6.08-6.15(1H,m), 7.05-7.18(4H,m)

The compounds of the present invention have strong renin-inhibitingactivities against a renin-angiotensin hypertensive system and thusexpected to be useful as curing agents of hypertention due to theprogress of the renin-angiotensin system.

We claim:
 1. An N-acylamino acid derivative of the following formula orits pharmaceutically acceptable salt: ##STR146## where m is an integerof 0 to 2;n is an integer or 0 to 3; R¹ represents a hydroxy-substitutedor unsubstituted C₁₋₅ alkyl group, C₃₋₆ cycloalkyl group, C₄₋₈cycloalkylalkyl group, C₆₋₁₀ aryl group or C₇₋₁₅ aralkyl group, R²represents a C₁₋₁₅ alkyl group, tetrahydronaphthylmethyl group,naphthylmethyl group, quinolylmethyl group, or a benzyl group which maybe substituted with a C₁₋₅ alkyl group; R³ and R⁵ represent hydrogen; R⁴represents a C₁₋₅ alkyl group which may be substituted with animidazolyl group; R⁶ represents a C₁₋₅ alkyl group, C₄₋₈ cycloalkylgroup, C₆₋₁₀ aryl group or C₇₋₁₅ aralkyl group; A is a group representedby the formula --CH(OH)--(CH₂)_(q) --R⁷ wherein q is 0, 1 or 2; and R⁷represents a morpholino group which is unsubstituted or substituted witha C₁₋₅ alkyl substituent.
 2. An N-acylamino acid derivative of thefollowing formula or its pharmaceutically acceptable salt: ##STR147##wherein m is an integer of 0 to 2;n is an integer of 0 to 3; R¹represents a hydroxy-substituted or unsubstituted C₁₋₅ alkyl group, C₃₋₆cycloalkyl group, C₄₋₈ cycloalkylalkyl group, C₆₋₁₀ aryl group or C₇₋₁₅aralkyl group, R² represents a quinolylmethyl group; R³ and R⁵ representhydrogen; R⁴ represents a C₁₋₅ alkyl group which may be substituted witha hydroxy group, carboxy group, amino group, C₂₋₅ alkylcarbonyloxygroup, C₁₋₅ alkylthio group or imidazolyl group; R⁶ represents a C₁₋₅alkyl group, C₄₋₈ cycloalkylalkyl group, C₆₋₁₀ aryl group or C₇₋₁₅aralkyl group; A is a group represented by the formula--CH(OH)--(CH₂)_(q) --R⁷ wherein q is 0, 1 or 2; and R⁷ represents amorpholino group which is unsubstituted or substituted with a C₁₋₅ alkylsubstituent.
 3. (2S,3R,4S)-4-{L-N.sup.α-[(2S)-3-ethylsulfonyl-2-(1-naphthylmethyl)propionyl]histidyl}amino-5cyclohexyl-1-morpholino-2,3-pentanediol.